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C# Windows Service not connecting to Brainbox device

I am new to C# and the code below is a mashup of a Microsoft tutorial and a simple program that I created (which works on its own), so I apologize now.
The service part appears to be working. Windows is running the service and I am getting event log messages saying that the service is running.
What I am not seeing is that the server is connected to the Brainbox device (192.168.10.174) I can see this by looking at the webpage of the Brainbox device. I am guessing that I am missing something really obvious. As the Brainbox_Data program runs perfectly well on its own in a console app.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.Common;
using System.Diagnostics;
using System.Linq;
using System.ServiceProcess;
using System.Text;
using System.Threading.Tasks;
using System.Timers;
using System.Configuration;
using Brainboxes.IO;
namespace MyNewService
{
public partial class MyNewService : ServiceBase
{
public MyNewService()
{
InitializeComponent();
eventLog1 = new System.Diagnostics.EventLog();
if (!System.Diagnostics.EventLog.SourceExists("MySource"))
{
System.Diagnostics.EventLog.CreateEventSource(
"MySource", "MyNewLog");
}
eventLog1.Source = "MySource";
eventLog1.Log = "MyNewLog";
}
protected override void OnStart(string[] args)
{
eventLog1.WriteEntry("In OnStart. NEW");
BrainboxData();
Timer timer = new Timer();
timer.Interval = 60000; // 60 seconds
timer.Elapsed += new ElapsedEventHandler(this.OnTimer);
timer.Start();
}
protected override void OnStop()
{
eventLog1.WriteEntry("In OnStop.");
}
private int eventId = 1;
public void OnTimer(object sender, ElapsedEventArgs args)
{
// TODO: Insert monitoring activities here.
eventLog1.WriteEntry("Monitoring the System", EventLogEntryType.Information, eventId++);
}
static void BrainboxData()
{
string provider = ConfigurationManager.AppSettings
["provider"];
string connectionString = ConfigurationManager.AppSettings
["connectionString"];
DbProviderFactory factory = DbProviderFactories.GetFactory(provider);
using (DbConnection connection = factory.CreateConnection())
{
connection.ConnectionString = connectionString;
connection.Open();
DbCommand command = factory.CreateCommand();
command.Connection = connection;
using (EDDevice ed = EDDevice.Create("192.168.10.174"))
{
ed.Label = "TrumpfE";
ed.Inputs[0].IOLineRisingEdge += (line, device, changeType) =>
{
command.CommandText = "INSERT INTO dbo.Brainbox_Data (datetimestamp, iolintimee, value, IPAddress) VALUES (GETDATE(),'" + line + "' , 1, '192.168.10.174')";
command.ExecuteNonQuery();
};
ed.Inputs[1].IOLineRisingEdge += (line, device, changeType) =>
{
command.CommandText = "INSERT INTO dbo.Brainbox_Data (datetimestamp, iolintimee, value, IPAddress) VALUES (GETDATE(),'" + line + "' , 0, '192.168.10.174')";
command.ExecuteNonQuery();
};
}
}
}
}
}
Any help would be greatly accepted.

Call an api from web application periodically ASP.NET Razor

Hy,
I'm trying to call api from my web application every hour and store data in my database.
This is my Code to call
public class GetNationFromAPI
{
public static async Task GetNation()
{
try
{
string connectionString = ConfigurationManager.ConnectionStrings["PW"].ConnectionString;
string url = ConfigurationManager.GetSection("url").ToString();//Get Url from appsettings.json
var response = await GetApi.GetClient.GetStringAsync(url);
var obj = JsonConvert.DeserializeObject<RootDataModel>(response);
using SqlConnection con = new SqlConnection(connectionString);
string deleteQuery = "Delete From Nation";
SqlCommand com = new SqlCommand(deleteQuery, con);
con.Open();
com.ExecuteNonQuery();
con.Close();
string nationtblname = ConfigurationManager.GetSection("nationtblname").ToString();//Get Table name from appsettings.json
string nationquery = string.Format("insert into {0} (Nation_Id, Nation, Alliance_Id, Alliance, Score, VacMode, Alliance_Position, soldiers, tanks, aircraft, ships) " +
"Values (#nation_Id, #nation, #alliance_Id, #alliance, #alliance_Position, #score, #vacMode,#v_mode_turns, #soldiers, #tanks, #aircraft, #ships)", nationtblname);
foreach (var nations in obj.data)
{
SqlCommand comm = new SqlCommand(nationquery, con);
con.Open();
comm.Parameters.AddWithValue("#nation_Id", nations.nation_id);
comm.Parameters.AddWithValue("#nation", nations.nation);
comm.Parameters.AddWithValue("#alliance_Id", nations.alliance_id);
comm.Parameters.AddWithValue("#alliance", nations.alliance);
comm.Parameters.AddWithValue("#alliance_Position", nations.alliance_position);
comm.Parameters.AddWithValue("#score", nations.score);
comm.Parameters.AddWithValue("#vacMode", nations.v_mode);
comm.Parameters.AddWithValue("#v_mode_turns", nations.v_mode_turns);
comm.Parameters.AddWithValue("#soldiers", nations.soldiers);
comm.Parameters.AddWithValue("#tanks", nations.tanks);
comm.Parameters.AddWithValue("#aircraft", nations.aircraft);
comm.Parameters.AddWithValue("#ships", nations.ships);
comm.ExecuteNonQuery();
con.Close();
};
}
catch
{
throw new Exception();
}
}
}
Initially I did it from console application and it worked fine however I want my web app to do automatically every hour so I tried this in startup class of web application.
public class Startup
{
private static Timer atimer;
public static async Task Main()
{
atimer = new Timer
{
Interval = 3600000
};
atimer.Elapsed += await OnTimedEventAsync();
atimer.AutoReset = true;
atimer.Enabled = true;
}
private static async Task<ElapsedEventHandler> OnTimedEventAsync()
{
GetApi.InitializeClient();
await GetNationFromAPI.GetNation();
throw new Exception();
}
When I start my application and prompted to localhost and try to view nation. I get object reference not set to an instance of object instead of blank web page.

SQL dependency event not being triggered

First time working with SQL Dependency... but after having gone over several examples I feel as I am doing everything correct. I've checked that the Broker is Enabled. I've further checked that my query is correct. I am not receiving any exceptions at all! All and all everything seems as it should work... but it is not, and I have no idea how to begin to troubleshoot it without any exceptions being thrown.
Any help would be VERY much appreciated!
Here is my class:
public class NotificationEvent
{
private delegate void RateChangeNotification(DataTable table);
private SqlDependency dependency;
string ConnectionString = #"ConnectionString";
string UserName = Environment.UserName;
public async void StartNotification()
{
SqlDependency.Start(this.ConnectionString, "UserNotificationsQueue");
SqlConnection connection = new SqlConnection(this.ConnectionString);
await connection.OpenAsync();
SqlCommand command = new SqlCommand();
command.Connection = connection;
command.CommandType = CommandType.Text;
command.CommandText = string.Format("SELECT [NotificationID],[UserFrom],[UserTo],[DateTimeSent],[Notification] FROM [dbo].[PersonnellNotifications]", UserName);
command.Notification = null;
this.dependency = new SqlDependency(command, "Service=PostUserNotificationsQueue;", Int32.MaxValue);
dependency.OnChange += new OnChangeEventHandler(this.SqlDependencyOnChange);
await command.ExecuteReaderAsync();
}
private void SqlDependencyOnChange(object sender, SqlNotificationEventArgs eventArgs)
{
if (eventArgs.Info == SqlNotificationInfo.Invalid)
{
Console.WriteLine("The above notification query is not valid.");
}
else
{
Console.WriteLine("Notification Info: " + eventArgs.Info);
Console.WriteLine("Notification source: " + eventArgs.Source);
Console.WriteLine("Notification type: " + eventArgs.Type);
}
}
public void StopNotification()
{
SqlDependency.Stop(this.ConnectionString, "QueueName");
}
}
I am initializing this from another classes IniatializeComponent() as seen:
private void InitializeComponent()
{
// Initialize SQL Dependancy
ne.StartNotification();
}

I have just tested following in my Code and Its working good. I have simplified your code. Please see if this is working and you are getting a call in OnNotificationChange on Db Change.
public async void RegisterForNotification()
{
var connectionString = #"ConnectionString";
using (var connection = new SqlConnection(connectionString))
{
await connection.OpenAsync();
var queryString = "Your Query String";
using (var oCommand = new SqlCommand(queryString, connection))
{
// Starting the listener infrastructure...
SqlDependency.Start(connectionString);
var oDependency = new SqlDependency(oCommand);
oDependency.OnChange += OnNotificationChange;
// NOTE: You have to execute the command, or the notification will never fire.
await oCommand.ExecuteReaderAsync();
}
}
}
private void OnNotificationChange(object sender, SqlNotificationEventArgs e)
{
Console.WriteLine("Notification Info: " + e.Info);
//Re-register the SqlDependency.
RegisterForNotification();
}

Are you setting SQLClientPermission? see:
https://learn.microsoft.com/en-us/dotnet/framework/data/adonet/sql/enabling-query-notifications
// Code requires directives to
// System.Security.Permissions and
// System.Data.SqlClient
private bool CanRequestNotifications()
{
SqlClientPermission permission =
new SqlClientPermission(
PermissionState.Unrestricted);
try
{
permission.Demand();
return true;
}
catch (System.Exception)
{
return false;
}
}

MySql executing a MySqlScript even when the connection has been closed

Is it possible for mysql to execute a script even when the connection has been closed?
I am using mysql community server , through a .NET connector API.
Was using c# to test out the API.
I have the following static class
using System;
using System.Data;
using MySql.Data;
using MySql.Data.MySqlClient;
public static class DataBase
{
static string connStr = "server=localhost;user=root;port=3306;password=*******;";
static MySqlConnection conn;
public static bool Connect()
{
conn = new MySqlConnection(connStr);
try
{
conn.Open();
}
catch (Exception Ex)
{
ErrorHandler(Ex);
return false;
}
return true;
}
public static int ExecuteScript(string scripttext) // returns the number of statements executed
{
MySqlCommand cmd = conn.CreateCommand();
cmd.CommandText = scripttext;
MySqlScript script;
int count= 0;
try
{
script = new MySqlScript(conn, cmd.CommandText);
script.Error += new MySqlScriptErrorEventHandler(script_Error);
script.ScriptCompleted += new EventHandler(script_ScriptCompleted);
script.StatementExecuted += new MySqlStatementExecutedEventHandler(script_StatementExecuted);
count = script.Execute();
}
catch (Exception Ex)
{
count = -1;
ErrorHandler(Ex);
}
return count;
}
# region EventHandlers
static void script_StatementExecuted(object sender, MySqlScriptEventArgs args)
{
string Message = "script_StatementExecuted";
}
static void script_ScriptCompleted(object sender, EventArgs e)
{
string Message = "script_ScriptCompleted!";
}
static void script_Error(Object sender, MySqlScriptErrorEventArgs args)
{
string Message = "script_Error: " + args.Exception.ToString();
}
# endregion
public static bool Disconnect()
{
try
{
conn.Close();
}
catch (Exception Ex)
{
ErrorHandler(Ex);
return false;
}
return true;
}
public static void ErrorHandler(Exception Ex)
{
Console.WriteLine(Ex.Source);
Console.WriteLine(Ex.Message);
Console.WriteLine(Ex.ToString());
}
}
and I am using the following code to test out this class
using System;
using System.Data;
namespace Sample
{
public class Sample
{
public static void Main()
{
if (DataBase.Connect() == true)
Console.WriteLine("Connected");
if (DataBase.Disconnect() == true)
Console.WriteLine("Disconnected");
int count = DataBase.ExecuteScript("drop database sample");
if (count != -1)
{
Console.WriteLine(" Sample Script Executed");
Console.WriteLine(count);
}
Console.ReadKey();
}
}
}
I noticed that even though I have closed my MySql connection using Disconnect() - which i have defined, mysql continues to execute the command i give next and no error is generated.
I feel like I am doing something wrong, as an error should be generated when i try to execute a script on a closed connection.
Is it a problem in my code/logic or some flaw in mysql connector?
I did check through the mysql workbench whether the command was executed properly and it was.

This is a decompile of MySqlScript.Execute code....
public unsafe int Execute()
{
......
flag = 0;
if (this.connection != null)
{
goto Label_0015;
}
throw new InvalidOperationException(Resources.ConnectionNotSet);
Label_0015:
if (this.query == null)
{
goto Label_002A;
}
if (this.query.Length != null)
{
goto Label_002C;
}
Label_002A:
return 0;
Label_002C:
if (this.connection.State == 1)
{
goto Label_0047;
}
flag = 1;
this.connection.Open();
....
As you can see, when you build the MySqlScript the connection passed is saved in an internal variable and before executing the script, if the internal connection variable is closed, the code opens it. Not checked but I suppose that it also closes the connection before exiting (notice that flag=1 before opening)
A part from this I suggest to change your code to avoid keeping a global MySqlConnection object. You gain nothing and risk to incur in very difficult bugs to track.
static string connStr = "server=localhost;user=root;port=3306;password=*******;";
public static MySqlConnection Connect()
{
MySqlConnection conn = new MySqlConnection(connStr);
conn.Open();
return conn;
}
This approach allows to write code that use the Using Statement
public static int ExecuteScript(string scripttext) // returns the number of statements executed
{
using(MySqlConnection conn = Database.Connect())
using(MySqlCommand cmd = conn.CreateCommand())
{
cmd.CommandText = scripttext;
....
}
}
The Using statement will close and dispose the connection and the command freeing valuable resources and also in case of exception you will be sure to have the connection closed and disposed

Page_Load firing multiple times?

We have been dealing with an error for the last couple of days, so we created a small page (quick and dirty programming, my apologies in advance) that connects to the database, checks if a document exists, and displays some data related to the document. If there is an exception, an email is sent with the exception information and some log data.
Here's a simplified version of the code (short explanation below):
namespace My.Namespace
{
public partial class myClass : System.Web.UI.Page
{
private static SqlConnection conn = null;
private static SqlCommand command1 = null;
private static SqlCommand command2 = null;
private static string log = "";
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
try
{
log += "START\n";
string docId = Request.QueryString["docId"];
if (!String.IsNullOrEmpty(docName))
{
bool docExists = doesDocExist(docId);
if (docExists == true)
{
string docMetadata = getMetadata(docId);
Response.Write(docMetadata);
}
}
else
{
// display error message
}
}
catch (sqlException sqlex)
{
// process exception
sendErrorMessage(sqlex.Message);
}
catch (Exception ex)
{
// process exception
sendErrorMessage(ex.Message);
}
}
}
private static bool doesDocExist(string docId)
{
log += "In doesDocExist\n";
bool docExists = false;
try
{
// open db connection (conn)
string cmd = String.Format("SELECT COUNT(*) FROM docs WHERE id='{0}'", docId);
command1 = new SqlCommand(cmd, conn);
conn.Open();
var val = command1.ExecuteScalar();
int numberOfRows = int.Parse(val.ToString());
if (numberOfRows > 0) { docExists = true; }
}
finally
{
// close db connection (conn)
}
return docExists;
}
protected string getMetadata(string docId)
{
log += "In getMetadata\n";
string docMetadata = "";
try
{
// open db connection (conn)
string cmd = String.Format("SELECT metadata FROM docs WHERE id='{0}'", docID);
command2 = new SqlCommand(cmd, conn);
conn.Open();
SqlDataReader rReader = command2.ExecuteReader();
if (rReader.HasRows)
{
while (rReader.Read())
{
// process metadata
docMetadata += DOCMETADATA;
}
}
}
return docMetadata;
}
public static void sendErrorMessage(string messageText)
{
HttpContext.Current.Response.Write(messageText);
// Send string log via email
}
}
}
I know it's too long, so here is a quick description of it. We have a class with the Page_Load method and three other methods:
doesDocExists: returns a bool value indicating if an document ID is in the database.
getMetadata: returns a string with metadata related to the document.
sendErrorMessage: sends an email with a log generated during the page.
From Page_Load we call doesDocExists. If the value returned is true, then it calls getMetadata and displays the value on the screen. If there's any error, it is caught in the Page_Load and sent as an email.
The problem is that when there's an error, instead of getting an email with the log (i.e.: START - In Function1 - In Function2), the log appears 100 times in the email (i.e.: START - In Function1 - In Function2 - Start - In Function1 - In Function2 - START... and so on), as if Page_Load was fired that many times.
We read online (http://www.craigwardman.com/blog/index.php/2009/01/asp-net-multiple-page-load-problem/) that it could be because of the PostBack. So, we added the condition if (!Page.IsPostBack), but the result is still the same.
Is there any reason why Page_Load would be triggered multiple times? Or is it that we are doing something wrong with the log variable and/or the try/catch that causes this behavior?

The log may be long because you are declaring the string log as static. Does it need to be static?

private static SqlConnection conn = null;
private static SqlCommand command1 = null;
private static SqlCommand command2 = null;
private static string log = "";
The problem is that log is Singleton along with other properties.
Whenever you access that page, you append text to log property which ends up being START - In Function1 - In Function2 - Start - In Function1 - In Function2 - START... and so on
Base on your scenario, you do not need to use Singleton inside myClass.
FYI: Since I do not know the rest of your code, ensure to instantiate conn, command1, command2.

If your page load functions are execute twice because post back is possible when you clicking on the button or link, so should check it and run by the below
if (!IsPostBack)
{
try
{
log += "START\n";
string docId = Request.QueryString["docId"];
if (!String.IsNullOrEmpty(docName))
{
bool docExists = doesDocExist(docId);
if (docExists == true)
{
string docMetadata = getMetadata(docId);
Response.Write(docMetadata);
}
}
else
{
// display error message
}
}
catch (sqlException sqlex)
{
// process exception
sendErrorMessage(sqlex.Message);
}
catch (Exception ex)
{
// process exception
sendErrorMessage(ex.Message);
}
}
}