Contract.Assert Method (Boolean, String)


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Checks for a condition; if the condition is false, follows the escalation policy set by the analyzer and displays the specified message.

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

public static void Assert(
	bool condition,
	string userMessage


Type: System.Boolean

The conditional expression to test.

Type: System.String

A message to display if the condition is not met.

The default escalation policy is to notify the attached debugger about a contract failure or to display an Assert dialog box if a debugger is not attached. Optionally, the analyzer can be instructed to throw an exception. The userMessage parameter is passed to the debugger output. If userMessage is not a constant string literal, tools may not be able to read it.

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Available since 4.0
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
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