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Debug.Fail Method (String, String)

Emits an error message and a detailed error message.

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

[ConditionalAttribute("DEBUG")]
public static void Fail(
	string message,
	string detailMessage
)

Parameters

message
Type: System.String

A message to emit.

detailMessage
Type: System.String

A detailed message to emit.

The default behavior is that the DefaultTraceListener outputs the message to a message box when the application is running in user-interface mode and to the TraceListener instances in the Listeners collection.

NoteNote:

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 removing one from, the Listeners collection.

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

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

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

switch (option1) {
    case MyOption.First:
       result = 1.0;
       break;

    // Insert additional cases. 

    default:
       Debug.Fail("Unknown Option " + option1, "Result set to 1.0");
       result = 1.0;
       break;
 }

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.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0
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