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Rules to Better .NET Projects

Have you ever seen dialogs raised on the server-side? These dialogs would hang the thread they were on, and hang IIS until they were dismissed. In this case, you might use Trace.Fail or set AssertUIEnabled="true" in your web.config.

See Scott's blog Preventing Dialogs on the Server-Side in ASP.NET or Trace.Fail considered Harmful

 public static void ExceptionFunc(string strException)
{
    System.Diagnostics.Trace.Fail(strException);
}

Figure: Never use Trace.Fail

<configuration>
   <system.diagnostics>
      <assert AssertUIEnabled="true" logfilename="c:\log.txt" />
   </system.diagnostics>
</configuration>

Figure: Never set AssertUIEnabled="true" in web.config

<configuration>
   <system.diagnostics>
      <assert AssertUIEnabled="false" logfilename="c:\log.txt" />
   </system.diagnostics>
</configuration>

Figure: Should set AssertUIEnabled="false" in web.config