.NET Proxy Support - HTTPWebRequest - c#

Okay I need help, again! For some reason it is not working, no idea why.. nothing even appears on my catch request..
public void load(object sender, DoWorkEventArgs e)
{
int repeat = 1;
int proxyIndex = 1;
if (listBox1.Items.Count == proxyIndex) //If we're at the end of the proxy list
{
proxyIndex = 0; //Make the selected item the first item in the list
}
try
{
int i = 0;
while (i < listBox1.Items.Count)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(textBox1.Text);
string proxy = listBox1.Items[1].ToString();
string[] proxyArray = proxy.Split(':');
WebProxy proxyz = new WebProxy(proxyArray[0], int.Parse(proxyArray[1]));
request.Proxy = proxyz;
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
string str = reader.ReadToEnd();
}
}
/*HttpWebRequest request = (HttpWebRequest)WebRequest.Create(textBox1.Text);
string proxy = listBox1.Items[i].ToString();
string[] proxyArray = proxy.Split(':');
WebProxy proxyz = new WebProxy(proxyArray[0], int.Parse(proxyArray[1]));
request.Proxy = proxyz;
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream());
string str = reader.ReadToEnd();
Thread.Sleep(100);
{
if (str != null)
{
listBox2.Items.Add("Starting connection.");
Thread.Sleep(1000);
{
listBox2.Items.Add("Waiting..");
Thread.Sleep(500);
{
listBox2.Items.Add("Connection closed.");
repeat++;
continue;
}
}
}
else if (str == null)
{
listBox2.Items.Add("Reply was null, moving on.");
proxyIndex++;
repeat++;
}
}
*/
}
}
catch (Exception ex) //Incase some exception happens
{
MessageBox.Show(ex.Message);
return;
// listBox2.Items.Add("Error:" + ex.Message);
}
}
How can I get it to work?

It looks like you're trying to use a BackgroundWorker to perform this operation, and in the absence of any more detailed information on what isn't working, I'd guess it's because you aren't assigning any result or errors which can be picked up by main thread.
You should assign the results of the request in the case of success:
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
e.Result = reader.ReadToEnd();
}
Since you seem to be making multiple requests you should probably make the result a List<string> or similar.
You should remove the try/catch block and deal with any errors in the RunWorkerCompleted event of the BackgroundWorker:
private void BackgroundWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if(e.Error != null)
{
MessageBox.Show("Error in async operation: " + ex.Message);
}
else
{
//process results
}
}

Related

Application freezes while using IO C#

I don't know what causes the issue, but whenever I try to read from a text file in this situation, the application freezes.
private void btnCount_Click(object sender, EventArgs e)
{
int totalVotes = 0;
int votesFirst = 0;
int votesSecond = 0;
string firstClub;
string secondClub;
FileStream fs = null;
StreamReader sr = null;
if (tb1.Text == "" || tb2.Text == "")
{
MessageBox.Show("Fill in the fields");
}
else
{
firstClub = tb1.Text;
secondClub = tb2.Text;
try
{
fs = new FileStream("C:\\Users\\dluuk\\source\\repos\\PopularFootballClubs\\Polls\\bin\\Debug\\FootballClubs.txt", FileMode.Open, FileAccess.Read);
sr = new StreamReader(fs);
string s = sr.ReadLine();
while (s != null)
{
if (s.Contains(firstClub))
{
votesFirst++;
totalVotes++;
}
else if (s.Contains(secondClub))
{
votesSecond++;
totalVotes++;
}
}
}
catch (IOException ex)
{
MessageBox.Show(ex.Message);
}
catch (Exception)
{
MessageBox.Show("something wrong happened");
}
finally
{
lblTotal.Text = totalVotes.ToString();
lbl1.Text = votesFirst.ToString();
lbl2.Text = votesSecond.ToString();
if (sr != null) { sr.Close(); }
if (fs != null) { fs.Close(); }
}
}
}
I'm closing connection and the path is correct, because I don't get any exceptions at this current state so I really can't see the problem. Maybe you can help?
You aren't updating s at all, so your loop is infinite. It's reading the first line, then looping over and over again, using the same line each time because ReadLine() is not called again in the scope of the loop (and thus you never reach the end of the file - or even line 2).
You could change to something like this:
string s;
while ((s = sr.ReadLine()) != null)
{
if (s.Contains(firstClub))
{
votesFirst++;
totalVotes++;
}
else if (s.Contains(secondClub))
{
votesSecond++;
totalVotes++;
}
}
As a side note, you should put using statements around your Streams. They are disposable and you won't need to handle it manually.
while (s != null)
You never change s in the loop, so it gets stuck in an infinite loop. Update s at the end of the loop:
while (s != null)
{
// do stuff
s = sr.ReadLine();
}

Handling post requests in HttpListener

private void ListenerCallback(IAsyncResult ar)
{
_busy.WaitOne();
try
{
HttpListenerContext context;
try
{ context = _listener.EndGetContext(ar); }
catch (HttpListenerException)
{ return; }
if (_stop.WaitOne(0, false))
return;
var sr = new StreamReader(context.Request.InputStream);
string x = sr.ReadToEnd();
Console.WriteLine("{0} {1}", context.Request.HttpMethod, x);
//context.Response.SendChunked = true;
using (TextWriter tw = new StreamWriter(context.Response.OutputStream))
{
//for (int i = 0; i < 5; i++)
{
//tw.WriteLine("<p>{0} # {1}</p>", i, DateTime.Now);
tw.WriteLine("<html><head></head><body>");
tw.WriteLine("Server Response");
tw.WriteLine("</body></html>");
tw.Flush(); //Catch http exception if client exists halfway through
//Thread.Sleep(1000);
}
}
}
finally
{
if (_maxThreads == 1 + _busy.Release())
_idle.Set();
}
}
Above is my code, I can go to the URL with Chrome and few the reply even though the server shows it takes 2 get requests, I want to be able to handle POST requests, when I send a post request it reads it properly but the client doesn't get the reply.
You should add ctx.Response.ContentLength64=....
(you may also need ctx.Response.Close())

Linkchecker doesnt print any broken urls

I'm having problems creating a linkchecker, I'd like to have it online mainly for learning..
The problem is that i first had it as a console application which worked kinda well (i got broken urls to show i debug console), now that i'm trying to get it to web I'm having trouble..
How do I go about getting this into the document? I'm kinda stumped at the moment..
public partial class Default2 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
public bool UrlIsValid(string url)
{
try
{
HttpWebRequest request = HttpWebRequest.Create(url) as HttpWebRequest;
request.Timeout = 5000; //set the timeout to 5 seconds to keep the user from waiting too long for the page to load
request.Method = "HEAD"; //Get only the header information -- no need to download any content
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
int statusCode = (int)response.StatusCode;
if (statusCode >= 100 && statusCode < 400) //Good requests
{
return true;
}
else if (statusCode >= 500 && statusCode <= 510) //Server Errors
{
string cl = (String.Format("The remote server has thrown an internal error. Url is not valid: {0}", url));
// Debug.WriteLine(cl, Convert.ToString(url));
return false;
}
}
catch (WebException ex)
{
if (ex.Status == WebExceptionStatus.ProtocolError) //400 errors
{
return false;
}
else
{
string cl = String.Format("Unhandled status [{0}] returned for url: {1}", ex.Status, url);
/// Debug.WriteLine(cl, Convert.ToString(ex));
}
}
catch (Exception ex)
{
object cl = String.Format("Could not test url {0}.", url);
Debug.WriteLine(cl, Convert.ToString(ex));
}
return false;
}
private void button1_Click(object sender, EventArgs e)
{
WebClient wc = new WebClient();
string checker = wc.DownloadString("http://administration.utbildningssidan.se/linkcheck.aspx");
while (checker.Contains("<a href="))
{
int checkstart = checker.IndexOf("<a href=") + 8;
int checkstop = checker.IndexOf(">", checkstart);
string validator = checker.Substring(checkstart, checkstop - checkstart);
// perform the check
if (!UrlIsValid(validator)) { Debug.WriteLine(validator); }
checker = checker.Substring(checkstop + 1);
}
}
}
Hope you understand what I want accomplished, having a hard time making sense right now..
I think you want Response.Write() in place of your Debug.WriteLine() methods. OR, you could create a TextArea object in your markup and use myTextArea.Text += "Some text";

C# ProgressBar Threading mobile 6

I am programming an application for downloading articles from an SQL Database on the internet. I have programmed the Website for managing the articles. Now I'm downloading the article List in gzip Format and then I decompress them to a xml-File. When I'm done I want to insert the articles to the mobile phone. This works great. Now I want to add an progress Bar to see the state of the insertion. I tried with Threading but this doesn't work. I'm posting some pieces of code from my application and also the progressUpdate methods.
private void btn_send_Click(object sender, EventArgs e)
{
label1.Text = "Download started";
string ArticlesURL = "URLTOSITE";
InvokeAsync(ArticlesURL);
}
private void InvokeAsync(string URL)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(URL);
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.AllowWriteStreamBuffering = true;
allDone.Reset();
request.BeginGetRequestStream(new AsyncCallback(ReadArticlesCallback), request);
allDone.WaitOne();
request.BeginGetResponse(new AsyncCallback(ResponseArticlesCallback), request);
}
private static void ReadArticlesCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
//End the operation.
Stream postSream = request.EndGetRequestStream(asynchronousResult);
string postData = "articles=test";
//Convert the string into a byte array.
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
//Write to the request stream.
postSream.Write(byteArray, 0, postData.Length);
postSream.Close();
allDone.Set();
}
private static void ResponseArticlesCallback(IAsyncResult asynchronousResult)
{
Form1 f = new Form1();
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
HttpWebResponse resp = (HttpWebResponse)request.EndGetResponse(asynchronousResult);
Stream streamResponse = resp.GetResponseStream();
StreamReader streamRead = new StreamReader(streamResponse);
string responseString = streamRead.ReadToEnd();
nbrArticles = Convert.ToInt16(responseString);
// Close the stream object.
streamResponse.Close();
streamRead.Close();
// Release the HttpWebResponse.
resp.Close();
f.truncate_articles();
f.get_articles();
}
private void get_articles()
{
string url = "URLTOSITE";
int startPoint = 0;
DownloadZipFile((object)startPoint, url);
DecompressFile();
getXmlAndInsertInDB();
}
private void getXmlAndInsertInDB()
{
int total = nbrArticles;
int count = total / 100; //How much articles are 1 percent
int i = 0;
String barcode = "";
String name = "";
bool state = false;
XmlTextReader reader = new XmlTextReader("Program Files\\SmartDeviceProject1\\articles.xml");
while (reader.Read())
{
switch (reader.NodeType)
{
case XmlNodeType.Element: //The node is an element
while (reader.MoveToNextAttribute()) //Get the attributes like barcode, lastname, firstname, pincode
switch (reader.Name)
{
case "barcode":
barcode = reader.Value.ToString();
state = false;
break;
case "name":
name = reader.Value.ToString();
state = true;
break;
}
break;
}
if (state == true)
{
cmd.CommandText = "INSERT INTO articles(barcode, name) " +
"VALUES('" + barcode + "','" + name + "');";
cmd.ExecuteNonQuery();
state = false;
i++;
if (i == count)
{
Thread t = new Thread(new ThreadStart(this.incrementProgressBar));
t.Start();
//incrementProgressBar();
i = 0;
}
}
}
reader.Close();
}
private void updateProgressBarMethod(int progress)
{
if (progressBar1.InvokeRequired)
{
//It was called from a non UI thread so we create a delegate
//and have the UI Thread call this method again
UpdateProgressBar = new UpdateProgressBarDelegate(updateProgressBarMethod);
this.Invoke(UpdateProgressBar, progress);
}
else
{
//Called from the UI Thread OK to update
//update your progress bar here
progressBar1.Value += progress;
}
}
private void incrementProgressBar()
{
//Call the method to update progress Bar on UI thread
//we do not need a delegate here that will be taken care of
//in the method
updateProgressBarMethod(1);
Application.DoEvents();
}
I think the problem is that I am using Callbacks. I have read that the Callbacks are also starting Threads. So I think the problem is there but I can't solve it.
I've found another very good site for threading with mobile applications: Updating the User Interface from a Worker Thread
Now with the new code, the debugger stops always at the same piece of code without any notification or exception :( Here is my new code:
if (i == count)
{
this.info_percent = "Synchro " + step.ToString() + "%";
this.Invoke(new EventHandler(WorkerUpdate)); //The Debugger stops here!
i = 0;
step++;
Thread.Sleep(700);
}
public void WorkerUpdate(object sender, EventArgs e)
{
this.lbl_percent.Text = this.info_percent;
this.lbl_percent.Update();
this.progressBar1.Value = step;
this.progressBar1.Update();
}
The Debugger stops at: this.Invoke(new EventHandler(WorkerUpdate));
I would suggest using the Background worker class. I had a similar problem and implemented the Background worker and it fixed my problem. Hopefully it will fix yours also
http://www.dotnetperls.com/backgroundworker
http://msdn.microsoft.com/en-us/library/cc221403(v=vs.95).aspx
I found another thread discussing this and thought it would help:
Is there a BackgroundWorker replacement for .NET Compact Framework 3.5?
Your code will always hang at this point:
if (i == count)
{
this.info_percent = "Synchro " + step.ToString() + "%";
this.Invoke(new EventHandler(WorkerUpdate)); //The Debugger stops here!
i = 0;
step++;
Thread.Sleep(700);
}
Make these changes:
public delegate void MethodInvoker(); // this is not defined in CF
if (i == count)
{
this.info_percent = "Synchro " + step.ToString() + "%";
object sender = null; // make this whatever you want/need
EventArgs e = new EventArgs();
if (this.InvokeRequired) {
MethodInvoker mi = delegate { WorkerUpdate(sender, e); } };
this.BeginInvoke(mi);
} else {
WorkerUpdate(sender, e);
}
i = 0;
step++;
// Thread.Sleep(700); Why is this here?
}
This should prevent those obnoxious freezes.

From C# to Android via Socket. Can't find my mistake

The problem - I can't get this functions working. I see in LogCat that socket is connected to c# server, but I don't see received data. What I'm doing wrong?
Here is c# function with MessageBoxes for checking:
private void receiveConnection(){
Socket myHandler = null;
bool isConnected = false;
while (true)
{
if (!isConnected)
{
myHandler = wSocket.Accept();
isConnected = true;
MessageBox.Show("We have client!");
}
if (sendDataToAndroid)
{
try
{
sendDataToAndroid = false;
NetworkStream stream = new NetworkStream(myHandler);
StreamWriter sw = new StreamWriter(stream);
string myMsg = "";
myMsg += temp_F.Length + " ";
temp_F[0] = 3.151F;
temp_F[1] = 1.415F;
temp_F[2] = 5.572F;
temp_F[3] = 6.320F;
for (int i = 0; i < temp_F.Length; i++)
{
myMsg += temp_F[i] + " ";
}
byte[] msg = Encoding.ASCII.GetBytes(myMsg);
MessageBox.Show("Data to send: " + myMsg);
try
{
myHandler.Send(msg);
MessageBox.Show("Data has been sent!");
}
catch (Exception e) {
MessageBox.Show("Error while sending data!");
}
}
catch (Exception e)
{
isConnected = false;
myHandler.Close();
myHandler = null;
MessageBox.Show("Error while sending data...");
}
}
}
}
And here is Android function which is always trying to receive data:
public class SendThread implements Runnable {
public void run()
{
Socket socket = null;
BufferedReader in = null;
while (true)
{
// Loop until connected to server
while (socket == null){
try{
socket = new Socket ("192.168.137.1", 808);
}
catch (Exception e) {
socket = null;
}
}
// Get from the server
try {
Log.d("Connection: ", "connected");
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
String line = null;
while ((line = in.readLine()) != null) {
Log.d("Socket:", line);
NumberFormat nf = new DecimalFormat ("990,0");
String[] tokens = line.split(" ");
int currTempSize = Integer.parseInt(tokens[0]);
currentTemp = new double[currTempSize];
for (int i = 0; i < currTempSize; i++)
currentTemp[i] = (Double) nf.parse(tokens[i+1]);
//Toast.makeText(getApplicationContext(), "Received data:", duration)
for (int i = 0; i < currTempSize; i++){
Log.d("Converted data: currentTemp["+i+"] = ", currentTemp[i]+"");
}
}
}
catch (Exception e) {
socket = null;
in = null;
Log.d("Connection: ", "lost.");
}
}
}
}
Your Java code reads a line at a time but you never sent a line terminator from C#.
You could append one to myMsg manually, or you could use the sw.WriteLine() method on your StreamWriter (which don't otherwise seem to be using). After calling sw.WriteLine() you will probably have to call sw.Flush().

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