introduction to interop: some good article from net

I was looking for some good tutorial on net for com interop, i got following nice articles:
http://msdn.microsoft.com/en-us/library/kew41ycz%28VS.71%29.aspx

http://radio.weblogs.com/0105852/stories/2002/11/14/introductionTonetComInterop.html


http://msdn.microsoft.com/en-us/magazine/cc163494.aspx

http://www.15seconds.com/Issue/040721.htm

Published in: on January 20, 2010 at 12:30 pm  Leave a Comment  
Tags: , , , ,

The CLR has been unable to transition from COM context 0xXXXXXX to COM context 0xXXXXXX for 60 seconds. The thread that owns the destination context/apartment is most likely either doing a non pumping wait or processing a very long running operation without pumping Windows messages

Error Message:

“The CLR has been unable to transition from COM context 0x1979d8 to COM context 0x197868 for 60 seconds. The thread that owns the destination context/apartment is most likely either doing a non pumping wait or processing a very long running operation without pumping Windows messages. This situation generally has a negative performance impact and may even lead to the application becoming non responsive or memory usage accumulating continually over time. To avoid this problem, all single threaded apartment (STA) threads should use pumping wait primitives (such as CoWaitForMultipleHandles) and routinely pump messages during long running operations.”

You get this nasty error message and your life is sucked. This happens when you are debugging your application and using breakpoints.

Fix For The Problem:

Go to menu Debug->Exception-> a form appears. Then in Managed Debug Assistants section, just uncheck the ContextSwitchDeadlock.

Note:

If you are not able to see Exception MenuItem in debug menu, then add it from Tools->Customize->Commands.

A very (extremely) simple ASP .Net Hello World example, Just for fun…

I was going through an ASP.Net book, and thought of writing extremely simply Hello World example. This will give an insight of how simple and small page you can write using ASP .Net.

For each example I have given asp .net code and corresponding browser generated code.

Example1

<%@ Page Language="c#"  %>
<%Response.Write("Hello World");>

Brower Source:

Hello World

Example2:

<%@ Page Language="c#" %>
<script runat="server">
void SayHello()
{
Response.Write("Hello World !");
}
</script>
<html>
<body>
<% SayHello(); %>
</body>
</html>

Brower Source:

<html>
<body>
Hello World !
</body>
</html>

.Net and MySQL: Example of using MySQL and .Net: A simple example of useing Connector/Net 5.2 to connect with MySQL from .Net

Follow this process:

  1. Download Connector/Net 5.2.
  2. Unzip the binaries. You will find 3-4 dlls along with other files.
  3. Add reference to mysql.data.dll, in your project.
  4. You can connect to MySQL throw code, as described below:

String conString = “server=server_name; user id=user_name;

password=password; database=db_name; pooling=false;”;

String queryString = “select * from employee;”;

using (MySqlConnection mySqlConnection = new MySqlConnection(conString))

{

using (MySqlDataAdapter adapter = new MySqlDataAdapter(queryString, mySqlConnection))

{

DataTable dt = new DataTable();

adapter.Fill(dt);

dataGridView1.DataSource = dt;

}

}

Published in: on July 27, 2009 at 8:39 pm  Leave a Comment  
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C# .Net and MySQL: how to connect MySQL from .Net ?

I was wondering how to connect MySQL with .Net then i got following solutions in net:

http://www.15seconds.com/issue/050407.htm

http://dev.mysql.com/tech-resources/articles/dotnet/index.html#ADO.NET

There might be several other articles describing several other ways to connect with MySQL from .Net but I found Connector/Net 5.2 from MySQL good.