DefaultTraceListener.Fail Method (String)


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Emits or displays a message and a stack trace for an assertion that always fails.

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

public override void Fail(
	string message


Type: System.String

The message to emit or display.

By default, this method sends the message parameter and a stack trace to a message box (when the application runs in user-interface mode) and to the DefaultTraceListener instance.

The following code example writes an error message to a DefaultTraceListener using the Fail(String) method. The method also writes the message to the console if a user interface is not available.

// Report that the required argument is not present.
const string ENTER_PARAM = "Enter the number of " +
          "possibilities as a command line argument.";
if (!defaultListener.AssertUiEnabled)

.NET Framework
Available since 1.1
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