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Simple TCP Chat Client Code Review and Questions

I am relatively new to programming and I took it upon myself to make a simple chat application; think AIM from back in the day. This is more of a request for a code review than a list of questions. For the most part, the application works with a few minor errors which I will highlight below. Please see the code from the project: https://github.com/N8STROMO/Basic-Chat-Tcp as well as the code listed below. Questions are embedded along the way. Thanks for any help you may be able to provide!
Here is the Server Code: Server.cs
namespace Server
{
public class Server
{
// This is the port that the server will be listening on
const int PORT = 500;
// This is where the usernames and their connections will be held
readonly Dictionary<string, ServerUserConnection> userToConnections = new Dictionary<string, ServerUserConnection>();
readonly TcpListener listener;
public static void Main()
{
// Constructor for the ChatServer
Server server = new Server();
while(true)
{
Thread.Sleep(1); // Temp to keep alive
}
}
/// <summary>
/// Listens for data from clients
/// </summary>
public Server()
{
listener = TcpListener.Create(PORT);
listener.Start();
WaitForConnections();
}
/// <summary>
/// Begins an asynchronous operation to accept an incoming connection attempt
/// </summary>
private void WaitForConnections()
{
listener.BeginAcceptTcpClient(OnConnect, null);
}
/// <summary>
/// This method is executed asynchronously
/// Connects the client to the server
/// Broadcasts the user to client to be displayed on the chatform
/// Then waits for another connection to be established
/// </summary>
/// <param name="ar"></param>
void OnConnect(IAsyncResult ar)
{
//Asynchronously accepts an incoming connection attempt and creates a new TcpClient to handle remote host communication.
TcpClient client = listener.EndAcceptTcpClient(ar);
Console.WriteLine("Connected");
ReceiveUser(client);
BroadcastUserList();
WaitForConnections();
}
/// <summary>
/// Connects a user to the server and adds them to the dictionary userToConnections
/// </summary>
/// <param name="client"></param>
public void ReceiveUser(TcpClient client)
{
ServerUserConnection connection = new ServerUserConnection(this, client); // Constructor
userToConnections.Add(connection.userName, connection);
}
/// <summary>
/// For each user that is connected append the userList to include that user
/// TODO Do not need to keep a running list of users; send the user over then throw it away
/// </summary>
void BroadcastUserList()
{
string userList = "";
foreach(var connection in userToConnections)
{
userList += $"{connection.Value.userName},";
}
SendMsgToAll(MessageType.UserList, null, userList);
}
/// <summary>
/// Pushes out messages to the connected clients
/// </summary>
/// <param name="type"></param>
/// <param name="user"></param>
/// <param name="message"></param>
public void SendMsgToAll(MessageType type, ServerUserConnection user, string message)
{
Console.WriteLine($"{user?.userName}: {message}");
foreach(var connection in userToConnections)
{
Console.WriteLine($"Sending to {connection.Value.userName}");
Utils.SendInformation(type, connection.Value.stream, message);
}
}
}
}
Here is the ServerUserConnection.cs: I am having trouble understanding how the inheritance here works and what the base keyword does.
namespace Server
{
public class ServerUserConnection : UserConnection
{
readonly Server server;
/// <summary>
/// Facilitates connection
/// </summary>
/// <param name="server"></param>
/// <param name="client"></param>
public ServerUserConnection(Server server, TcpClient client) : base(client, GetUsername(client)) // Inherits from UserConnection()
{
this.server = server;
}
private static string GetUsername(TcpClient client)
{
NetworkStream stream = client.GetStream();
if(stream.CanRead)
{
// Receives infromation from the stream, determines MessageType, and returns username
string userName = Utils.ReceiveInformation(stream, client, out MessageType type);
Console.WriteLine(userName);
return userName;
}
return null;
}
/// <summary>
///
/// </summary>
/// <param name="type"></param>
/// <param name="message"></param>
protected override void OnRead(MessageType type, string message)
{
if(type != MessageType.ChatMessage)
{
return;
}
server.SendMsgToAll(MessageType.ChatMessage, this, $"{userName} {message}");
}
}
}
Here is the Client Code: Client.cs
namespace Client
{
public class ChatClient
{
private const int PORT = 500;
TcpClient client = new TcpClient();
public ChatForm chatForm;
public ClientUserConnection userConnection;
string data;
[STAThread]
public static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
var client = new ChatClient();
var form = new ConnectForm(client);
Application.Run(form);
}
/// <summary>
/// This is called when the ConnectForm btnSubmit is pressed.
/// </summary>
/// <param name="ipAddress"></param>
/// <param name="userName"></param>
public void ConnectToServer(string ipAddress, string userName)
{
client.Connect(ipAddress, PORT);
SendUserName(userName);
}
/// <summary>
/// Sends user to the server
/// </summary>
public void SendUserName(string user)
{
userConnection = new ClientUserConnection(client, this, user);
Utils.SendInformation(MessageType.Connect, client.GetStream(), user);
}
/// <summary>
/// Sends a message to the server
/// </summary>
/// <param name="msg"></param>
public void SendMessage(string msg)
{
Utils.SendInformation(MessageType.ChatMessage, userConnection.stream, msg);
}
}
}
Here is the ClientUserConnection.cs: Is there a way to refactor or optimize this so that instead of keeping a running list of messages just send the message over and throw it away? Again, the same question about inheritance.
public class ClientUserConnection : UserConnection
{
public readonly Client.ChatClient chatClient;
public string message = "";
public string userListText;
/// <summary>
///
/// </summary>
/// <param name="client"></param>
/// <param name="chatClient"></param>
/// <param name="userName"></param>
public ClientUserConnection(TcpClient client, Client.ChatClient chatClient, string userName) : base(client, userName) // Inherits from UserConnection()
{
this.chatClient = chatClient;
}
/// <summary>
/// When the data is reads determine what kind of message it is
/// Parse/split out the message and user; display only relevant data
/// TODO Do not need to keep a running list of messages; send the message over then throw it away
/// </summary>
/// <param name="type"></param>
/// <param name="message"></param>
protected override void OnRead(MessageType type, string message)
{
if(type == MessageType.ChatMessage)
{
int iSpace = message.IndexOf(" ");
if(iSpace < 0)
{
// if error
return;
}
string from = message.Substring(0, iSpace);
string chatMessage = message.Substring(iSpace + 1, message.Length - iSpace - 1);
this.message += $"[{from}]: {chatMessage}{Environment.NewLine}";
}
else if(type == MessageType.UserList)
{
string[] userList = message.Split(',');
string userListText = "";
for(int i = 0; i < userList.Length; i++)
{
userListText += $"{userList[i]}{Environment.NewLine}";
}
this.userListText = userListText;
}
}
}
There are also three files within a class library that are used within this project:
This is the MessageType.cs:
public enum MessageType
{
Connect, UserList, ChatMessage
}
This is the UserConnection.cs: I still need to deal with disconnecting users. If one of the chat forms is closed, it crashes the application.
public abstract class UserConnection
{
public readonly TcpClient client;
public readonly NetworkStream stream;
public readonly string userName;
byte[] data;
/// <summary>
///
/// </summary>
/// <param name="client"></param>
/// <param name="userName"></param>
public UserConnection(TcpClient client, string userName)
{
this.client = client;
this.userName = userName;
stream = client.GetStream();
data = new byte[client.ReceiveBufferSize];
WaitForData();
}
/// <summary>
///
/// </summary>
private void WaitForData()
{
Console.WriteLine("Wait");
stream.BeginRead(data, 0, data.Length, OnReadData, null);
}
/// <summary>
/// SocketException: An existing connection was forcibly closed by the remote host
/// </summary>
/// <param name="ar"></param>
void OnReadData(IAsyncResult ar)
{
Console.WriteLine("Read");
int result = stream.EndRead(ar); // TODO disconnect & error handling
Console.WriteLine("Read done");
if(result <= 0)
{
Console.WriteLine("Error reading");
return;
}
string message = Utils.ReceiveInformation(data, result, out MessageType type);
OnRead(type, message);
WaitForData();
}
/// <summary>
///
/// </summary>
/// <param name="type"></param>
/// <param name="message"></param>
protected abstract void OnRead(MessageType type, string message);
}
This is the Utils.cs: I am having trouble understanding how there are two methods called ReceiveInformation() and how they interact with each other
public class Utils
{
/// <summary>
///
/// </summary>
/// <param name="stream"></param>
/// <param name="connection"></param>
/// <param name="type"></param>
/// <returns></returns>
public static string ReceiveInformation(NetworkStream stream, TcpClient connection, out MessageType type)
{
byte[] bytes = new byte[connection.ReceiveBufferSize];
int length = stream.Read(bytes, 0, bytes.Length);
return ReceiveInformation(bytes, length, out type);
}
/// <summary>
///
/// </summary>
/// <param name="bytes"></param>
/// <param name="length"></param>
/// <param name="type"></param>
/// <returns></returns>
public static string ReceiveInformation(byte[] bytes, int length, out MessageType type)
{
string data = Encoding.ASCII.GetString(bytes, 0, length);
int iSpace = data.IndexOf(' ');
if(iSpace < 0)
{
// TODO
}
string typeString = data.Substring(0, iSpace);
type = (MessageType)Enum.Parse(typeof(MessageType), typeString);
string message = data.Substring(iSpace + 1, data.Length - iSpace - 1);
return message;
}
/// <summary>
///
/// </summary>
/// <param name="type"></param>
/// <param name="stream"></param>
/// <param name="message"></param>
public static void SendInformation(MessageType type, NetworkStream stream, string message)
{
Byte[] sendBytes = Encoding.UTF8.GetBytes($"{type} {message}");
stream.Write(sendBytes, 0, sendBytes.Length);
}
}

Subclassing all classes in a 'chain' of subclasses

I came up with this example to clarify my question
We start with a base class
/// <summary>
/// Just a silly example class
/// </summary>
class CFileStream
{
protected readonly string FilePath;
public CFileStream(string filePath)
{
FilePath = filePath;
}
public virtual void Write(string s)
{
var stream = GetStream(FilePath);
//etc
}
/// <summary>
/// Take filePath as an argument to make subclassing easier
/// </summary>
protected virtual FileStream GetStream(string filePath)
{
return new FileStream(filePath, FileMode.OpenOrCreate);
}
}
Create a subclass for it
/// <summary>
/// Building on top of CFileStream, created an encrypted version
/// </summary>
class CFileStreamEncrypted : CFileStream
{
private readonly string _key;
public CFileStreamEncrypted(string filePath, string key):base(filePath)
{
_key = key;
}
/// <summary>
/// For added complexity, let's also wrap a possible excepton
/// </summary>
public override void Write(string s)
{
try
{
base.Write(s);
}
catch (ImaginaryCryptoException ex)
{
throw new ImaginaryCustomException("bladibla", ex);
}
}
/// <summary>
/// Wrap the base stream in an imaginary crypto class
/// </summary>
protected override FileStream GetStream(string filePath)
{
return new CImaginaryCryptoStream(base.GetStream(filePath), _key);
}
}
Now we wish to create a second subclass, but one that works with the initial filewriter as well as the encrypted version.
The first one makes sense
/// <summary>
/// Building on top of CFileStream, created an auto-split version
/// </summary>
class CFileStreamSplit : CFileStream
{
public CFileStreamSplit(string filePath)
: base(filePath)
{
}
protected int Counter;
/// <summary>
/// Close stream and move to next file at the appropriate time(s)
/// </summary>
public override void Write(string s)
{
do
{
Stream stream;
if (ImaginaryBooleanMustSplit)
stream = GetStream(FilePath);
//etc
} while (ImaginaryBooleanDataLeftToWrite);
}
/// <summary>
/// Get base stream but with altered filePath
/// </summary>
protected override FileStream GetStream(string filePath)
{
return base.GetStream(GetNextpath(filePath));
}
/// <summary>
/// Ignore proper extension / file-exists etc.
/// </summary>
protected virtual string GetNextpath(string filePath)
{
return filePath + ++Counter;
}
}
The second one (below this) is completely duplicate code, except for the constructor which now also requires the encryption key.
/// <summary>
/// Build the same auto-split version but this time on top of the encrypted subclass
/// </summary>
class CFileStreamSplitEncrypted : CFileStreamEncrypted
{
public CFileStreamSplitEncrypted(string filePath, string key)
: base(filePath, key)
{
}
/*
* Note that there are no changes below this line
*/
protected int Counter;
/// <summary>
/// Close stream and move to next file at the appropriate time(s)
/// </summary>
public override void Write(string s)
{
do
{
Stream stream;
if (ImaginaryBooleanMustSplit)
stream = GetStream(FilePath);
//etc
} while (ImaginaryBooleanDataLeftToWrite);
}
/// <summary>
/// Get base stream but with altered filePath
/// </summary>
protected override FileStream GetStream(string filePath)
{
return base.GetStream(GetNextpath(filePath));
}
/// <summary>
/// Ignore proper extension / file-exists etc.
/// </summary>
protected virtual string GetNextpath(string filePath)
{
return filePath + ++Counter;
}
}
There are of course a lot of ways to reduce the amount of duplicate code here, but I have yet to find 'the best' way, if there even is such a thing. So; what is the least time-consuming, cleanest, most flexible way to get a round this issue in your opinion/experience?

For the different modifications a decent way to go may be composition over inheritance. Set up your classes to only be responsible for a single thing, taking in a base stream on constructions.
interface ICFileStream
{
void Write(string s);
FileStream GetStream(string filePath);
}
/// <summary>
/// Just a silly example class
/// </summary>
class CFileStream: ICFileStream
{
protected readonly string FilePath;
public CFileStream(string filePath)
{
FilePath = filePath;
}
public void Write(string s)
{
var stream = GetStream(FilePath);
//etc
}
/// <summary>
/// Take filePath as an argument to make subclassing easier
/// </summary>
protected FileStream GetStream(string filePath)
{
return new FileStream(filePath, FileMode.OpenOrCreate);
}
}
/// <summary>
/// Building on top of CFileStream, created an encrypted version
/// </summary>
class CFileStreamEncrypted : ICFileStream
{
private readonly string _key;
private readonly ICFileStream _stream;
public CFileStreamEncrypted(string key, ICFileStream stream)
{
_key = key;
_stream = stream;
}
/// <summary>
/// For added complexity, let's also wrap a possible excepton
/// </summary>
public void Write(string s)
{
try
{
_stream.Write(s);
}
catch (ImaginaryCryptoException ex)
{
throw new ImaginaryCustomException("bladibla", ex);
}
}
/// <summary>
/// Wrap the base stream in an imaginary crypto class
/// </summary>
protected FileStream GetStream(string filePath)
{
return new CImaginaryCryptoStream(_stream.GetStream(filePath), _key);
}
}
class CFileStreamSplit : ICFileStream
{
private readonly ICFileStream _stream;
public CFileStreamSplit(ICFileStream stream)
{
_stream = stream;
}
protected int Counter;
/// <summary>
/// Close stream and move to next file at the appropriate time(s)
/// </summary>
public void Write(string s)
{
do
{
Stream stream;
if (ImaginaryBooleanMustSplit)
stream = GetStream(FilePath);
//etc
} while (ImaginaryBooleanDataLeftToWrite);
}
/// <summary>
/// Get base stream but with altered filePath
/// </summary>
protected FileStream GetStream(string filePath)
{
return _stream.GetStream(GetNextpath(filePath));
}
/// <summary>
/// Ignore proper extension / file-exists etc.
/// </summary>
protected string GetNextpath(string filePath)
{
return filePath + ++Counter;
}
}
So when you want a splitting-crypto-filestream:
new CFileStreamSplit(new CFileStreamEncrypted("crypto-awesome-key", new CFileStream("C:\\blah...")));
This is more flexible so when you want to add LoggingCFileStream for example you don't need to add a separate class for each combination.

C# 2.0 Multi-threading with a plug-in architecture

I have a well established console application in c# 2.0 that uses plugin architecture.
As of right now, the program uses basic multi-threading that can run several instances. The threads are created and continue on until the application is stopped.
Each instance can load its own variety of plugins and configured separately.
Plugins are inherited from a base plugin. This system has been working like a charm for years.
The plugins are event driven, they all read various events to see if they are called upon, if not they return and let the next plugin read the events to see if they are called out to fire.
This system has been working for years. However, I would like to further the scope of multi-threading to allow the plugins to listen to the events in an asynchronous fashion rather than synchronous. One of the drawbacks of this setup is that once a plugin fires and does its work, it locks out the instance. When the next event is fired it has to wait for the previous work to be completed. Then it will allow the next process to take place.
What I would like it to do, is execute the plugin and not have to wait for the process to end before moving on to the next process to begin by an event.
I am stuck with .Net 2.0 for the time being, and must find a solution in that framework. I have looked at numerous examples and I can not find one that meets the criteria. One of the problems is that each plugin has its own time that it may take to process, and there is no way to count to track the percentage that the plugin is complete. The plugins will start and ends its process when it is done. Depending on the parameters of the event, and the plugin it can take any range of time to complete.
My question would be what would be the best way to handle multi-threading in this situation where plugins are executed by events. I have looked at pages such as http://msdn.microsoft.com/en-us/library/2e08f6yc(v=vs.80).aspx and I can figure out where I would be able to have an entry point in an event driven plugin architecture.
If anyone has any clue, I would appreciate it. The lack of multi-threading in this manner has been the Achilles' heel for this application for years.
Plugin base: These contain some functions that are triggered by events:
using System;
using VhaBot.Communication;
namespace VhaBot
{
/// <summary>
/// Plugin BaseClass, must be inherited by all plugins
/// </summary>
public abstract class PluginBase : MarshalByRefObject
{
private bool _locked;
private string _name;
private string _internalName;
private int _version;
private string _author;
private string[] _contributors;
private string _description;
private PluginState _defaultState;
private string[] _dependencies;
private Command[] _commands;
/// <summary>
/// Friendly display name of plugin
/// </summary>
/// <example>
/// <code>
/// this.Name = "Message of the Day";
/// </code>
/// </example>
public string Name
{
set
{
if (_locked)
{
throw new Exception();
}
_name = value;
}
get { return _name; }
}
/// <summary>
/// Internal name of the plugin
/// </summary>
/// <example>
/// <code>
/// this.InternalName = "VhMotd";
/// </code>
/// </example>
public string InternalName
{
set
{
if (_locked)
{
throw new Exception();
}
_internalName = value.ToLower();
}
get { return _internalName; }
}
/// <summary>
/// Pluigin Version
/// </summary>
/// <remarks>
/// Versions are stored as integers only. Version 1.0.0 would have a value of 100
/// </remarks>
/// <example>
/// <code>
/// this.Version = 100;
/// </code>
/// </example>
public int Version
{
set
{
if (_locked)
{
throw new Exception();
}
_version = value;
}
get { return _version; }
}
/// <summary>
/// Author of the plugin
/// </summary>
/// <example>
/// <code>
/// this.Author = "Vhab";
/// </code>
/// </example>
public string Author
{
set
{
if (_locked)
{
throw new Exception();
}
_author = value;
}
get { return _author; }
}
/// <summary>
/// List of contributors to the development of the plugin.
/// </summary>
/// <example>
/// <code>
/// this.Contributors = new string[] { "Iriche", "Kilmanagh" };
/// </code>
/// </example>
public string[] Contributors
{
set
{
if (_locked)
{
throw new Exception();
}
_contributors = value;
}
get
{
if (_contributors != null)
{
return _contributors;
}
return new string[0];
}
}
/// <summary>
/// Description of the plugin
/// </summary>
/// <example>
/// <code>
/// this.Description = "Provides an interface to the user to view who is online and/or on the private channel.";
/// </code>
/// </example>
public string Description
{
set
{
if (_locked)
{
throw new Exception();
}
_description = value;
}
get { return _description; }
}
/// <summary>
/// The default <see cref="VhaBot.PluginState" /> of the plugin
/// </summary>
/// <example>
/// <code>
/// this.DefaultState = PluginState.Installed;
/// </code>
/// </example>
/// <seealso cref="VhaBot.PluginState" />
public PluginState DefaultState
{
set
{
if (_locked)
{
throw new Exception();
}
_defaultState = value;
}
get { return _defaultState; }
}
/// <summary>
/// List of other plugins that a plugin is dependent on to function
/// </summary>
/// <remarks>
/// Plugins are referred to using their internal names. See <see cref="VhaBot.PluginBase.InternalName" />
/// </remarks>
/// <example>
/// <code>
/// this.Dependencies = new string[] { "vhItems" };
/// </code>
/// </example>
public string[] Dependencies
{
set
{
if (_locked)
{
throw new Exception();
}
_dependencies = value;
}
get
{
if (_dependencies != null)
{
return _dependencies;
}
return new string[0];
}
}
public Command[] Commands
{
set
{
if (_locked)
{
throw new Exception();
}
_commands = value;
}
get
{
if (_commands != null)
{
return _commands;
}
return new Command[0];
}
}
internal void Init()
{
_locked = true;
}
/// <summary>
/// A plugin has loaded in response to <see cref="VhaBot.ShellModules.Plugins.Load" />
/// </summary>
/// <param name="bot"></param>
/// ///
/// <remarks>Code inside this method will be executed when a plugin is loading</remarks>
public virtual void OnLoad(BotShell bot)
{
}
/// <summary>
/// A plugin has unloaded in response to <see cref="VhaBot.ShellModules.Plugins.Unload" />
/// </summary>
/// <param name="bot"></param>
/// <remarks>Code inside this method will be executed when a plugin is unloading</remarks>
public virtual void OnUnload(BotShell bot)
{
}
/// <summary>
/// A plugin has installed in response to <see cref="VhaBot.ShellModules.Plugins.Install" />
/// </summary>
/// <param name="bot"></param>
public virtual void OnInstall(BotShell bot)
{
}
/// <summary>
/// A plugin as been uninstalled in response to <see cref="VhaBot.ShellModules.Plugins.Uninstall" />
/// </summary>
/// <param name="bot"></param>
public virtual void OnUninstall(BotShell bot)
{
}
/// <summary>
/// A plugin has been upgraded (Unused)
/// </summary>
/// <param name="bot"></param>
/// <param name="version"></param>
/// <remarks>This function is not active</remarks>
public virtual void OnUpgrade(BotShell bot, Int32 version)
{
}
/// <summary>
/// Response to a command
/// </summary>
/// <param name="bot"></param>
/// <param name="e"></param>
public virtual void OnCommand(BotShell bot, CommandArgs e)
{
}
/// <summary>
/// Response to an unauthorized command
/// </summary>
/// <param name="bot"></param>
/// <param name="e"></param>
public virtual void OnUnauthorizedCommand(BotShell bot, CommandArgs e)
{
}
/// <summary>
/// Response to a command help query <see cref="VhaBot.ShellModules.Commands.GetHelp." />
/// </summary>
/// <param name="bot"></param>
/// <param name="command"></param>
/// <returns></returns>
/// <remarks>Code inside this method will be executed when help is requested</remarks>
public virtual string OnHelp(BotShell bot, string command)
{
return null;
}
/// <summary>
/// Response to a custom configuration
/// </summary>
/// <param name="bot"></param>
/// <param name="key"></param>
/// <returns></returns>
public virtual string OnCustomConfiguration(BotShell bot, string key)
{
return null;
}
/// <summary>
/// Response to a plugin message
/// </summary>
/// <param name="bot"></param>
/// <param name="message"></param>
public virtual void OnPluginMessage(BotShell bot, PluginMessage message)
{
}
/// <summary>
/// Response to a bot message
/// </summary>
/// <param name="bot"></param>
/// <param name="message"></param>
public virtual void OnBotMessage(BotShell bot, BotMessage message)
{
}
/// <summary>
/// Returns display name of bot and current version
/// </summary>
/// <returns></returns>
public override string ToString()
{
return Name + " v" + Version;
}
/// <summary>
/// There is no information to document this command
/// </summary>
/// <param name="bot"></param>
/// <param name="args"></param>
public void FireOnCommand(BotShell bot, CommandArgs args)
{
try
{
if (args.Authorized)
OnCommand(bot, args);
else
OnUnauthorizedCommand(bot, args);
}
catch (Exception ex)
{
CommandArgs e = args;
var window = new RichTextWindow(bot);
window.AppendTitle("Error Report");
window.AppendHighlight("Error: ");
window.AppendNormal(ex.Message);
window.AppendLinkEnd();
window.AppendLineBreak();
window.AppendHighlight("Source: ");
window.AppendNormal(ex.Source);
window.AppendLinkEnd();
window.AppendLineBreak();
window.AppendHighlight("Target Site: ");
window.AppendNormal(ex.TargetSite.ToString());
window.AppendLinkEnd();
window.AppendLineBreak();
window.AppendHighlight("Stack Trace:");
window.AppendLineBreak();
window.AppendNormal(ex.StackTrace);
window.AppendLinkEnd();
window.AppendLineBreak();
bot.SendReply(e,
"There has been an error while executing this command »» " +
window.ToString("More Information"));
BotShell.Output("[Plugin Execution Error] " + ex);
}
}
}
}
Events Class:
namespace VhaBot.ShellModules
{
/// <summary>
/// VhaBot Events
/// </summary>
public class Events
{
public event BotStateChangedHandler BotStateChangedEvent;
public event ChannelJoinEventHandler ChannelJoinEvent;
public event UserJoinChannelHandler UserJoinChannelEvent;
public event UserLeaveChannelHandler UserLeaveChannelEvent;
public event UserLogonHandler UserLogonEvent;
public event UserLogoffHandler UserLogoffEvent;
public event PrivateMessageHandler PrivateMessageEvent;
public event PrivateChannelMessageHandler PrivateChannelMessageEvent;
public event ChannelMessageHandler ChannelMessageEvent;
public event MemberAddedHandler MemberAddedEvent;
public event MemberRemovedHandler MemberRemovedEvent;
public event MemberUpdatedHandler MemberUpdatedEvent;
public event AltAddedHandler AltAddedEvent;
public event AltRemovedHandler AltRemovedEvent;
/// <summary>
/// A message was sent to the IRC channel in response to a <see cref="VhaBot.BotShell.SendIrcMessage" /> request
/// </summary>
public event IrcMessageHandler IrcMessageEvent;
public event ConfigurationChangedHandler ConfigurationChangedEvent;
internal void OnBotStateChanged(BotShell bot, BotStateChangedArgs e)
{
if (BotStateChangedEvent != null)
try
{
BotStateChangedEvent(bot, e);
}
catch
{
}
}
internal void OnChannelJoin(BotShell bot, ChannelJoinEventArgs e)
{
if (ChannelJoinEvent != null)
try
{
ChannelJoinEvent(bot, e);
}
catch
{
}
}
internal void OnUserJoinChannel(BotShell bot, UserJoinChannelArgs e)
{
if (UserJoinChannelEvent != null)
try
{
UserJoinChannelEvent(bot, e);
}
catch
{
}
}
internal void OnUserLeaveChannel(BotShell bot, UserLeaveChannelArgs e)
{
if (UserLeaveChannelEvent != null)
try
{
UserLeaveChannelEvent(bot, e);
}
catch
{
}
}
internal void OnUserLogon(BotShell bot, UserLogonArgs e)
{
if (UserLogonEvent != null)
try
{
UserLogonEvent(bot, e);
}
catch
{
}
}
internal void OnUserLogoff(BotShell bot, UserLogoffArgs e)
{
if (UserLogoffEvent != null)
try
{
UserLogoffEvent(bot, e);
}
catch
{
}
}
internal void OnPrivateMessage(BotShell bot, PrivateMessageArgs e)
{
if (PrivateMessageEvent != null)
try
{
PrivateMessageEvent(bot, e);
}
catch
{
}
}
internal void OnPrivateChannelMessage(BotShell bot, PrivateChannelMessageArgs e)
{
if (PrivateChannelMessageEvent != null)
try
{
PrivateChannelMessageEvent(bot, e);
}
catch
{
}
}
internal void OnChannelMessage(BotShell bot, ChannelMessageArgs e)
{
if (ChannelMessageEvent != null)
try
{
ChannelMessageEvent(bot, e);
}
catch
{
}
}
internal void OnMemberAdded(BotShell bot, MemberAddedArgs e)
{
if (MemberAddedEvent != null)
try
{
MemberAddedEvent(bot, e);
}
catch
{
}
}
internal void OnMemberRemoved(BotShell bot, MemberRemovedArgs e)
{
if (MemberRemovedEvent != null)
try
{
MemberRemovedEvent(bot, e);
}
catch
{
}
}
internal void OnMemberUpdated(BotShell bot, MemberUpdatedArgs e)
{
if (MemberUpdatedEvent != null)
try
{
MemberUpdatedEvent(bot, e);
}
catch
{
}
}
internal void OnAltAdded(BotShell bot, AltAddedArgs e)
{
if (AltAddedEvent != null)
try
{
AltAddedEvent(bot, e);
}
catch
{
}
}
internal void OnAltRemoved(BotShell bot, AltRemovedArgs e)
{
if (AltRemovedEvent != null)
try
{
AltRemovedEvent(bot, e);
}
catch
{
}
}
internal void OnConfigurationChanged(BotShell bot, ConfigurationChangedArgs e)
{
if (ConfigurationChangedEvent != null)
try
{
ConfigurationChangedEvent(bot, e);
}
catch
{
}
}
internal void OnIrcMessage(BotShell bot, IrcMessageArgs e)
{
if (IrcMessageEvent != null)
{
IrcMessageEvent(bot, e);
}
try
{
}
catch
{
}
}
}
}

I've got little to go on as your description of the system is a bit vague but I'll give it a shot.
From your description it seems you have some plugin, say
interface IPlugin {
PluginResult ReadAndExecuteEvents(Events e);
// Added asynchronous methods.
IAsyncResult BeginReadAndExecuteEvents(Events e, AsyncCallback cb, Object state);
PluginResult EndReadAndExecuteEvents(IAsyncResult result);
}
with
class PluginResult
{
public Boolean Stop;
// etc.
}
also you don't seem to be using .NET events, but rather some sort of Event class/enumeration.
Your old code seems to be something like:
foreach (var eventList in ReadEvents())
foreach (var plugin in pluginList)
if (plugin.ReadAndExecuteEvents(eventList).Stop)
break;
You can make this asynchronous doing something like:
foreach (var eventList in ReadEvents())
{
// It seems this is what you want, only one event processed at a time by an "instance"? So block here until unlocked.
LockProcess();
var pluginIndex = 0;
AsyncCallback handleResult = null;
handleResult = delegate(IAsyncResult result)
{
if (pluginList[pluginIndex].EndReadAndExecuteEvents(result).Stop)
goto STOP;
pluginIndex += 1;
if (pluginIndex == pluginList.Count)
goto STOP;
Events e = (Events)result.AsyncState;
pluginList[pluginIndex].BeginReadAndExecuteEvents(e, handleResult, e);
return;
STOP:
UnlockProcess();
};
pluginList[0].BeginReadAndExecuteEvents(eventList, handleResult, eventList);
}
So in .NET 2 style you could add some BeginXxx method and in its AsyncCallback do your stuff.
Of course it is up to the actual plugin to do its multithreading/asynchronisity, say if it writes a file by using BeginWrite to a FileStream etc.
I have conveniently ignored exception handling here.
So, to make your whole application use this asynchronisity you can put this code in a BeginRunEvents method, say, following the same "APM" pattern. You can then schedule this to the threadpool if you wish.
If this is not at all what you are looking for please provide some more code examples/info.

C# While Loop in Worker Thread for listening command and response

Overview of the problem:
I try to use a thread (while..loop) to listen a command from user. If user send a command, it will assign new value in the global variable which is in the class (LoopingWorkerThread).
I don't understand if I don't put the thread sleep value lower than 10 milliseconds, and I wouldn't get any response (it is in the ListenCommand method) . Look like the global parameter is being overwritten "_CommandReceived" in the method, probably the processor run to fast and ignore the value of the parameter had changed ("_CommandReceived").
Kindly comment if there is any better mechanism. I had lock it in the ListenCommand while loop.
The following are the codes:
public class LoopingWorkerThread
{
/// <summary>
/// Local main thread for LoopingWorkerThread
/// </summary>
private Thread t;
/// <summary>
/// Local parameter to identify the LoopingWorkerThread Is On
/// </summary>
private bool _IsOn;
/// <summary>
/// Local parameter to store command received from user
/// </summary>
private int _CommandReceived;
/// <summary>
/// Local object to use for locking the LoopingWorker Thread
/// </summary>
private object _LockListenCommand = new object();
/// <summary>
/// Properties of LoopingWorker Thread Is On
/// </summary>
public bool IsOn
{
get { return _IsOn; }
set { _IsOn = value; }
}
/// <summary>
/// Property of storing the command received from user
/// </summary>
public int CommandReceived
{
get { return _CommandReceived; }
set { _CommandReceived = value; }
}
/// <summary>
/// Delegate for OnResponse Event Handler
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
public delegate void OnResponseHandler(object sender, ResponseArg e);
/// <summary>
/// Event of OnResponse
/// </summary>
public event OnResponseHandler OnResponse;
/// <summary>
/// Constructor of LoopingWorkerThread Class
/// </summary>
public LoopingWorkerThread()
{
_IsOn = false;
}
/// <summary>
/// Method of LoopingWorkerThread Function
/// </summary>
private void ListenCommand()
{
lock (_LockListenCommand)
while (_IsOn)
{
switch (_CommandReceived)
{
case 0:
// Ignore default command
break;
case 1:
FireOnResponse("Received cmd 1, response [Hello One]");
break;
case 2:
FireOnResponse("Received cmd 2, response [Hello Two]");
break;
default:
FireOnResponse("Error. Received unidentified command - " + _CommandReceived.ToString());
break;
}
//Console.WriteLine("ThreadProc: Cmd:[{0}] - Response:{1}", _CommandReceived.ToString(), ReaderResponse);
// Reset or Clear the Command Received
_CommandReceived = 0;
// If the sleep less than 10 millisecond, it always don't catch the
// command received which assigned to 1 or 2. Don't understand, or is there
// any better method.
**Thread.Sleep(10);**
}
}
/// <summary>
/// Function of firing response event back to user
/// </summary>
/// <param name="message"></param>
private void FireOnResponse(string message)
{
ResponseArg myarg = new ResponseArg(message);
if (OnResponse != null)
OnResponse(this, myarg);
}
/// <summary>
/// Method of starting the LoopingWorkerThread
/// </summary>
public void Start()
{
_IsOn = true;
FireOnResponse("Main thread: Started.");
// The constructor for the Thread class requires a ThreadStart
// delegate that represents the method to be executed on the
// thread. C# simplifies the creation of this delegate.
t = new Thread(new ThreadStart(ListenCommand));
// Start ThreadProc. Note that on a uniprocessor, the new
// thread does not get any processor time until the main thread
// is preempted or yields. Uncomment the Thread.Sleep that
// follows t.Start() to see the difference.
t.Start();
//Thread.Sleep(0);
FireOnResponse("Main thread: Call Start().");
}
/// <summary>
/// Method of stopping the LoopingWorkerThread
/// </summary>
public void Stop()
{
_IsOn = false;
t.Join();
//t.Abort();
FireOnResponse("LoopingWorker Thread is stopped.");
}
/// <summary>
/// Method of sending command to the LoopingWorkerThread
/// </summary>
/// <param name="readercmd"></param>
public void SendCommand(int readercmd)
{
_CommandReceived = readercmd;
}
}

Your code works because Thread.Sleep produces the necessary memory barrier required to read _commandReceived correctly. If you remove the Thread.Sleep call then you also remove the implicit memory barrier. Obviously, this is not a good mechanism to rely on though.
More importantly you are going about this the wrong way. What you should be using is the producer-consumer pattern. This is pretty easy with the BlockingCollection class since it blocks the consumer on Take while the queue is empty.
public class Example
{
private BlockingCollection<int> commands = new BlockingCollection<int>();
public Example()
{
var thread = new Thread(Run);
thread.IsBackground = true;
thread.Start();
}
public void SendCommmand(int command)
{
commands.Add(command);
}
private void Run()
{
while (true)
{
int command = commands.Take();
ProcessCommand(command);
}
}
private void ProcessCommand(int command)
{
// Process the command here.
}
}
BlockingCollection is available for 3.5 as part of the Reactive Extensions download.

Try declaring the variable volatile. More about this on http://msdn.microsoft.com/en-us/library/x13ttww7.aspx

WatiN unreliable for repeated downloads?

WatiN seems to not handle repeated download dialogs consistently:
foreach (string file in lstFiles)
{
// continue if no download link
if (!ie.Element([search criteria]).Exists) continue;
var btnDownload = ie.Element([search criteria]);
string fullFilename = workingDir + "\\" + file;
FileDownloadHandler download = new FileDownloadHandler(fullFilename);
using (new UseDialogOnce(ie.DialogWatcher, download))
{
btnDownload.ClickNoWait();
download.WaitUntilFileDownloadDialogIsHandled(30);
download.WaitUntilDownloadCompleted(150);
ie.RemoveDialogHandler(download);
}
}
Basically, I loop through a list of filenames that I expect to be available and click the download button. This usually works, but after so many downloads (it varies, sometimes everything that's available downloads, sometimes nothing) it will hang while waiting to handle the dialog. The button's identified correctly, the download dialog appears, it just isn't detected and handled. It isn't site-specific as similar methods on other sites are also met with variable success. Anyone encounter this before and know of a resolution?
edit: Repeated downloads do not work whatsoever in Server 2008. In Win7, this happens randomly after one or more successful repeated downloads.

The problem appears because IE File Download Dialog consist of 2 windows. WatiN DialogWatcher gets all the system windows and tries to handle them in foreach loop. After handling first correct dialog window DialogWatcher gets the next window wich has the same properties and is a valid Download Dialog. DialogWatcher starts waiting until this window is visible but it closes immediately after previos window is handled.
My solution is to return from foreach loop after any dialog is handled:
#region WatiN Copyright (C) 2006-2011 Jeroen van Menen
//Copyright 2006-2011 Jeroen van Menen
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#endregion Copyright
using System;
using System.Collections.Generic;
using System.Threading;
using WatiN.Core.Exceptions;
using WatiN.Core.Interfaces;
using WatiN.Core.Logging;
using WatiN.Core.Native.InternetExplorer;
using WatiN.Core.Native.Windows;
using WatiN.Core.UtilityClasses;
namespace WatiN.Core.DialogHandlers
{
/// <summary>
/// This class handles alert/popup dialogs. Every second it checks if a dialog
/// is shown. If so, it stores it's message in the alertQueue and closses the dialog
/// by clicking the close button in the title bar.
/// </summary>
public class DialogWatcher : IDisposable
{
private static IList<DialogWatcher> dialogWatchers = new List<DialogWatcher>();
private bool _keepRunning = true;
private readonly IList<IDialogHandler> _handlers;
private readonly Thread _watcherThread;
private bool _closeUnhandledDialogs = Settings.AutoCloseDialogs;
public Window MainWindow { get; private set; }
/// <summary>
/// Gets the dialog watcher for the specified (main) internet explorer window.
/// It creates new instance if no dialog watcher for the specified window exists.
/// </summary>
/// <param name="mainWindowHwnd">The (main) internet explorer window.</param>
/// <returns></returns>
public static DialogWatcher GetDialogWatcher(IntPtr mainWindowHwnd)
{
var window = new Window(mainWindowHwnd);
Logger.LogDebug("GetDialogWatcher mainhwnd: " + window.Hwnd + ", " + window.Title);
var toplevelWindow = window.ToplevelWindow;
Logger.LogDebug("GetDialogWatcher mainhwnd: " + toplevelWindow.Hwnd + ", " + toplevelWindow.Title);
CleanupDialogWatcherCache();
var dialogWatcher = GetDialogWatcherFromCache(toplevelWindow);
// If no dialogwatcher exists for the ieprocessid then
// create a new one, store it and return it.
if (dialogWatcher == null)
{
dialogWatcher = new DialogWatcher(toplevelWindow);
dialogWatchers.Add(dialogWatcher);
}
return dialogWatcher;
}
public static DialogWatcher GetDialogWatcherFromCache(Window mainWindow)
{
// Loop through already created dialogwatchers and
// return a dialogWatcher if one exists for the given processid
foreach (var dialogWatcher in dialogWatchers)
{
if (dialogWatcher.MainWindow.Equals(mainWindow))
{
return dialogWatcher;
}
}
return null;
}
public static void CleanupDialogWatcherCache()
{
var cleanedupDialogWatcherCache = new List<DialogWatcher>();
foreach (var dialogWatcher in dialogWatchers)
{
if (!dialogWatcher.IsRunning)
{
dialogWatcher.Dispose();
}
else
{
cleanedupDialogWatcherCache.Add(dialogWatcher);
}
}
dialogWatchers = cleanedupDialogWatcherCache;
}
/// <summary>
/// Initializes a new instance of the <see cref="DialogWatcher"/> class.
/// You are encouraged to use the Factory method <see cref="DialogWatcher.GetDialogWatcherFromCache"/>
/// instead.
/// </summary>
/// <param name="mainWindow">The main window handle of internet explorer.</param>
public DialogWatcher(Window mainWindow)
{
MainWindow = mainWindow;
_handlers = new List<IDialogHandler>();
// Create thread to watch windows
_watcherThread = new Thread(Start);
// Start the thread.
_watcherThread.Start();
}
/// <summary>
/// Increases the reference count of this DialogWatcher instance with 1.
/// </summary>
public void IncreaseReferenceCount()
{
ReferenceCount++;
}
/// <summary>
/// Decreases the reference count of this DialogWatcher instance with 1.
/// When reference count becomes zero, the Dispose method will be
/// automatically called. This method will throw an <see cref="ReferenceCountException"/>
/// if the reference count is zero.
/// </summary>
public void DecreaseReferenceCount()
{
if (ReferenceCount > 0)
{
ReferenceCount--;
}
else
{
throw new ReferenceCountException();
}
if (ReferenceCount == 0)
{
Dispose();
}
}
/// <summary>
/// Adds the specified handler.
/// </summary>
/// <param name="handler">The handler.</param>
public void Add(IDialogHandler handler)
{
lock (this)
{
_handlers.Add(handler);
}
}
/// <summary>
/// Removes the specified handler.
/// </summary>
/// <param name="handler">The handler.</param>
public void Remove(IDialogHandler handler)
{
lock (this)
{
_handlers.Remove(handler);
}
}
/// <summary>
/// Removes all instances that match <paramref name="handler"/>.
/// This method determines equality by calling Object.Equals.
/// </summary>
/// <param name="handler">The object implementing IDialogHandler.</param>
/// <example>
/// If you want to use RemoveAll with your custom dialog handler to
/// remove all instances of your dialog handler from a DialogWatcher instance,
/// you should override the Equals method in your custom dialog handler class
/// like this:
/// <code>
/// public override bool Equals(object obj)
/// {
/// if (obj == null) return false;
///
/// return (obj is YourDialogHandlerClassNameGoesHere);
/// }
/// </code>
/// You could also inherit from <see cref="BaseDialogHandler"/> instead of implementing
/// <see cref="IDialogHandler"/> in your custom dialog handler. <see cref="BaseDialogHandler"/> provides
/// overrides for Equals and GetHashCode that work with RemoveAll.
/// </example>
public void RemoveAll(IDialogHandler handler)
{
while (Contains(handler))
{
Remove(handler);
}
}
/// <summary>
/// Removes all registered dialog handlers.
/// </summary>
public void Clear()
{
lock (this)
{
_handlers.Clear();
}
}
/// <summary>
/// Determines whether this <see cref="DialogWatcher"/> contains the specified dialog handler.
/// </summary>
/// <param name="handler">The dialog handler.</param>
/// <returns>
/// <c>true</c> if [contains] [the specified handler]; otherwise, <c>false</c>.
/// </returns>
public bool Contains(IDialogHandler handler)
{
lock (this)
{
return _handlers.Contains(handler);
}
}
/// <summary>
/// Gets the count of registered dialog handlers.
/// </summary>
/// <value>The count.</value>
public int Count
{
get
{
lock (this)
{
return _handlers.Count;
}
}
}
/// <summary>
/// Gets or sets a value indicating whether unhandled dialogs should be closed automaticaly.
/// The initial value is set to the value of <cref name="Settings.AutoCloseDialogs" />.
/// </summary>
/// <value>
/// <c>true</c> if unhandled dialogs should be closed automaticaly; otherwise, <c>false</c>.
/// </value>
public bool CloseUnhandledDialogs
{
get
{
lock (this)
{
return _closeUnhandledDialogs;
}
}
set
{
lock (this)
{
_closeUnhandledDialogs = value;
}
}
}
/// <summary>
/// Gets the (main) internet explorer window handle this dialog watcher watches.
/// </summary>
/// <value>The process id.</value>
public IntPtr MainWindowHwnd
{
get { return MainWindow.Hwnd; }
}
/// <summary>
/// Called by the constructor to start watching popups
/// on a separate thread.
/// </summary>
private void Start()
{
while (_keepRunning)
{
if (MainWindow.Exists())
{
var winEnumerator = new WindowsEnumerator();
var windows = winEnumerator.GetWindows(win => true);
foreach (var window in windows)
{
if (!_keepRunning) return;
if(HandleWindow(window))
break;
}
// Keep DialogWatcher responsive during 1 second sleep period
var count = 0;
while (_keepRunning && count < 5)
{
Thread.Sleep(200);
count++;
}
}
else
{
_keepRunning = false;
}
}
}
public bool IsRunning
{
get { return _watcherThread.IsAlive; }
}
public int ReferenceCount { get; private set; }
/// <summary>
/// Get the last stored exception thrown by a dialog handler while
/// calling the <see cref="IDialogHandler.HandleDialog"/> method of the
/// dialog handler.
/// </summary>
/// <value>The last exception.</value>
public Exception LastException { get; private set; }
/// <summary>
/// If the window is a dialog and visible, it will be passed to
/// the registered dialog handlers. I none if these can handle
/// it, it will be closed if <see cref="CloseUnhandledDialogs"/>
/// is <c>true</c>.
/// </summary>
/// <param name="window">The window.</param>
/// <returns>
/// <c>true</c> if dialog is handled by one of handlers; otherwise, <c>false</c>.
/// </returns>
public bool HandleWindow(Window window)
{
if (!window.IsDialog()) return false;
if (!HasDialogSameProcessNameAsBrowserWindow(window)) return false;
// This is needed otherwise the window Style will return a "wrong" result.
WaitUntilVisibleOrTimeOut(window);
// Lock the thread and see if a handler will handle
// this dialog window
lock (this)
{
foreach (var dialogHandler in _handlers)
{
try
{
if (dialogHandler.CanHandleDialog(window, MainWindow.Hwnd))
{
if (dialogHandler.HandleDialog(window)) return true;
}
}
catch (Exception e)
{
LastException = e;
Logger.LogAction((LogFunction log) => { log("Exception was thrown while DialogWatcher called HandleDialog: {0}",e.ToString()); });
}
}
// If no handler handled the dialog, see if the dialog
// should be closed automatically.
if (!CloseUnhandledDialogs || !MainWindow.Equals(window.ToplevelWindow)) return false;
Logger.LogAction((LogFunction log) => { log("Auto closing dialog with title: '{0}', text: {1}, style: ", window.Title, window.Message, window.StyleInHex); });
window.ForceClose();
}
return false;
}
private bool HasDialogSameProcessNameAsBrowserWindow(Window window)
{
var comparer = new Comparers.StringComparer(window.ProcessName, true);
return comparer.Compare(MainWindow.ProcessName);
}
private static void WaitUntilVisibleOrTimeOut(Window window)
{
// Wait untill window is visible so all properties
// of the window class (like Style and StyleInHex)
// will return valid values.
var tryActionUntilTimeOut = new TryFuncUntilTimeOut(TimeSpan.FromSeconds(Settings.WaitForCompleteTimeOut));
var success = tryActionUntilTimeOut.Try(() => window.Visible);
if (!success)
{
Logger.LogAction((LogFunction log) => { log("Dialog with title '{0}' not visible after {1} seconds.", window.Title, Settings.WaitForCompleteTimeOut); });
}
}
#region IDisposable Members
/// <summary>
/// Performs application-defined tasks associated with freeing, releasing, or
/// resetting unmanaged resources.
/// </summary>
public void Dispose()
{
lock (this)
{
_keepRunning = false;
}
if (IsRunning)
{
_watcherThread.Join();
}
Clear();
}
#endregion
}
}

My team ran into this as well while automating IE8 with WatiN. The problem seems to be with IE, possibly doing some time consuming house-cleaning. The work-around we ultimately used was to invoke a new instance of IE within the outer loop, disposing of it each iteration and then waiting for 5 seconds for whatever was going on in the background to resolve. It was a hack but got the job done.
foreach (var file in lstFiles)
{
string fullFilename = workingDir + "\\" + file;
using (var browser = new IE(fullFilename))
{
//page manipulations...
FileDownloadHandler download = new FileDownloadHandler(fullFilename);
using (new UseDialogOnce(browser.DialogWatcher, download))
{ //lnkFile.ClickNoWait();
download.WaitUntilFileDownloadDialogIsHandled(15);
download.WaitUntilDownloadCompleted(150);
}
}
Thread.Sleep(5000);
}