System.Diagnostics.Contracts.Contract.Requires Method

Specifies a precondition contract for the enclosing method or property, and displays a message if the condition for the contract fails.

Syntax

[System.Diagnostics.Conditional("CONTRACTS_FULL")]
[System.Runtime.ConstrainedExecution.ReliabilityContract(System.Runtime.ConstrainedExecution.Consistency.WillNotCorruptState, System.Runtime.ConstrainedExecution.Cer.MayFail)]
public static void Requires (bool condition, string userMessage)

Parameters

condition
The conditional expression to test.
userMessage
The message to display if the condition is false.

Remarks

  • This method call must be at the beginning of a method or property, before any other code.

  • This contract is exposed to clients; therefore, it must only reference members that are at least as visible as the enclosing method.

  • Use this method instead of the Contract.Requires``1(bool, string) method when backward compatibility does not force you to throw a particular exception.

Requirements

Namespace: System.Diagnostics.Contracts
Assembly: mscorlib (in mscorlib.dll)
Assembly Versions: 4.0.0.0