Tracing tracks and presents the execution details about a Web request. For trace data to be visible in a rendered page, you must enable tracing at the page or application level.

Tracing on a page is disabled by default. To enable tracing for a page, use the @ Page directive <% @ Page trace="true" %>. To enable tracing for an entire application, you must enable it in the application's configuration file, Web.config, which resides in the root directory of the application. For more information, see ASP.NET Tracing Overview.

The following code example demonstrates accessing the TraceContext..::.IsEnabled property and the TraceContext..::.Write method through the Trace property. This code calls the Write method only when tracing is enabled for the Page object. If it is not enabled, this code will not run, which can help reduce overhead for your application.

If (Trace.IsEnabled) Then

  Dim I As Integer
  For I = 0 To DS.Tables("Categories").Rows.Count - 1

    Trace.Write("ProductCategory",DS.Tables("Categories").Rows(I)(0).ToString())
  Next
End If

if (Trace.IsEnabled)
{
  for (int i=0; i<ds.Tables["Categories"].Rows.Count; i++)
  {
    Trace.Write("ProductCategory",ds.Tables["Categories"].Rows[i][0].ToString());
  }
}

.NET Framework

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

Other Resources