Trace.Fail Method

Definition

Namespace:

System.Diagnostics

Assembly:

System.Diagnostics.TraceSource.dll

Emits an error message.

Overloads

Fail(String)	Emits the specified error message.
Fail(String, String)	Emits an error message, and a detailed error message.

Fail(String)

Source:

Trace.cs

Emits the specified error message.

public:
 static void Fail(System::String ^ message);

[System.Diagnostics.Conditional("TRACE")]
public static void Fail (string? message);

[<System.Diagnostics.Conditional("TRACE")>]
static member Fail : string -> unit

Public Shared Sub Fail (message As String)

Parameters

message

String

A message to emit.

Attributes

ConditionalAttribute

Examples

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

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

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

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

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

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;
}

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

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

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

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>, the <remove>, 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.

See also

• Debug
• Trace
• BooleanSwitch
• TraceSwitch
• TraceListener
• DefaultTraceListener
• ConditionalAttribute

Fail(String, String)

Source:

Trace.cs

Emits an error message, and a detailed error message.

public:
 static void Fail(System::String ^ message, System::String ^ detailMessage);

[System.Diagnostics.Conditional("TRACE")]
public static void Fail (string? message, string? detailMessage);

[<System.Diagnostics.Conditional("TRACE")>]
static member Fail : string * string -> unit

Public Shared Sub Fail (message As String, detailMessage As String)

Parameters

message

String

A message to emit.

detailMessage

String

A detailed message to emit.

Attributes

ConditionalAttribute

Examples

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

catch ( Exception^ ) 
{
  #if defined(TRACE)
  Trace::Fail( String::Format( "Invalid value: {0}", value ),
      "Resetting value to newValue." );
   #endif
   value = newValue;
}

catch (Exception)
{
    Trace.Fail("Invalid value: " + value.ToString(),
       "Resetting value to newValue.");
    value = newValue;
}

Catch
    Trace.Fail("Invalid value: " & value.ToString(), _
        "Resetting value to newValue.")
    value = newValue
End Try

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

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

   // Insert additional cases.

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

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

    // Insert additional cases.

    default:
        Trace.Fail("Unsupported option " + option, "Result set to 1.0");
        result = 1.0;
        break;
}

Select Case option1
    Case OptionConsts.First
        result = 1.0
    
    ' Insert additional cases.
    Case Else
        Trace.Fail("Unsupported option " & option1, "Result set to 1.0")
        result = 1.0
End Select

Remarks

The default behavior is for the default trace listener to output the message parameter and the detailedMessage 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>, the <remove>, 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.

See also

• Debug
• Trace
• BooleanSwitch
• TraceSwitch
• TraceListener
• DefaultTraceListener
• ConditionalAttribute