Tracing in ASP.NET Web Pages (Visual Studio)
ASP.NET allows you to view diagnostic information about a request for an ASP.NET page. Tracing also allows you to write debug statements directly in your code without having to remove them from your application when it is deployed to production servers. You can write variables or structures in a page, assert whether a condition is met, or simply trace through the execution path of your page or application. You can view tracing information appended to the end of a page, in a separate trace viewer, or both ways.
The topics in this section describe how tracing works, how to manage tracing, and how to integrate ASP.NET tracing with .NET system diagnostics.