Trace.Fail Method (String) (System.Diagnostics)

.NET Framework Class Library

Trace..::.Fail Method (String)

Emits the specified error message.

Namespace: System.Diagnostics
Assembly: System (in System.dll)

Syntax

Visual Basic (Declaration)

<ConditionalAttribute("TRACE")> _
Public Shared Sub Fail ( _
    message As String _
)

Visual Basic (Usage)

Dim message As String

Trace.Fail(message)

[ConditionalAttribute("TRACE")]
public static void Fail(
    string message
)

Visual C++

[ConditionalAttribute(L"TRACE")]
public:
static void Fail(
    String^ message
)

JScript

public static function Fail(
    message : String
)

Parameters

message: Type: System..::.String
A message to emit.

Remarks

The default behavior for the default trace listener is to output the message parameter to a message box when the application runs in user-interface mode, and to the TraceListener instances in the Listeners collection.

Note:
The display of the message box is dependent on the presence of the DefaultTraceListener. If the DefaultTraceListener is not in the Listeners collection, the message box is not displayed. The DefaultTraceListener can be removed by the <clear> Element for <listeners> for <trace>, the <remove> Element for <listeners> for <trace>, or by calling the Clear method on the Listeners property (System.Diagnostics.Trace.Listeners.Clear()).

Note:

The display of the message box is dependent on the presence of the DefaultTraceListener. If the DefaultTraceListener is not in the Listeners collection, the message box is not displayed. The DefaultTraceListener can be removed by the <clear> Element for <listeners> for <trace>, the <remove> Element for <listeners> for <trace>, or by calling the Clear method on the Listeners property (System.Diagnostics.Trace.Listeners.Clear()).

You can customize this behavior by adding a TraceListener to, or by removing one from, the Listeners collection.

Examples

The following example uses the Fail method to print a message during exception handling.

Visual Basic

Catch
    Trace.Fail("Unknown Option " + option1 + ", using the default.")
End Try

catch (Exception) {
    Trace.Fail("Unknown Option " + option + ", using the default.");
}

Visual C++

catch ( Exception^ ) 
{
   #if defined(TRACE)
   Trace::Fail( "Unknown Option " + option + ", using the default." );
   #endif
}

JScript

catch(e : Exception)
{
    @if(@TRACE)
    Trace.Fail("Cannot find SpecialController.")
    @end
}

You can also use the Fail method in a switch statement.

Visual Basic

Select Case option1
    Case OptionConsts.First
        result = 1.0

    ' Insert additional cases.
    Case Else
        Trace.Fail(("Unknown Option " & option1))
        result = 1.0
End Select

switch (option) {
    case Option.First:
       result = 1.0;
       break;

    // Insert additional cases.
    default:
       Trace.Fail("Unknown Option " + option);
       result = 1.0;
       break;
}

Visual C++

switch ( option )
{
   case Option::First:
      result = 1.0;
      break;

   // Insert additional cases.

   default:
      #if defined(TRACE)
      Trace::Fail(String::Format("Unknown Option {0}", option));
      #endif
      result = 1.0;
      break;
}

JScript

switch(option)
{
    case 1:
        result = 1.0
        break

    // Insert additional cases.

    default:
        @if(@TRACE)
        Trace.Fail("Unexpected value: " + option)
        @end
        result = 0.0
}

Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information