ContractArgumentValidatorAttribute Class
Enables the factoring of legacy if-then-throw code into separate methods for reuse, and provides full control over thrown exceptions and arguments.
Assembly: mscorlib (in mscorlib.dll)
| Name | Description | |
|---|---|---|
![]() | ContractArgumentValidatorAttribute() | Initializes a new instance of the ContractArgumentValidatorAttribute class. |
| Name | Description | |
|---|---|---|
![]() | Equals(Object) | This API supports the product infrastructure and is not intended to be used directly from your code. Returns a value that indicates whether this instance is equal to a specified object.(Inherited from Attribute.) |
![]() | GetHashCode() | Returns the hash code for this instance.(Inherited from Attribute.) |
![]() | GetType() | |
![]() | IsDefaultAttribute() | When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.(Inherited from Attribute.) |
![]() | Match(Object) | When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.(Inherited from Attribute.) |
![]() | ToString() | Returns a string that represents the current object.(Inherited from Object.) |
| Name | Description | |
|---|---|---|
![]() ![]() | _Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr) | Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from Attribute.) |
![]() ![]() | _Attribute.GetTypeInfo(UInt32, UInt32, IntPtr) | Retrieves the type information for an object, which can be used to get the type information for an interface.(Inherited from Attribute.) |
![]() ![]() | _Attribute.GetTypeInfoCount(UInt32) | Retrieves the number of type information interfaces that an object provides (either 0 or 1).(Inherited from Attribute.) |
![]() ![]() | _Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr) | Provides access to properties and methods exposed by an object.(Inherited from Attribute.) |
If your code uses explicit if-then-throw code to validate parameters, you may be employing helper methods that perform checks and throw particular exceptions on failure, as shown in the following example.
In this example, Execute has an elective precondition specifying that the parameter value should not be null. To enable the contract tools to recognize that the call to ValidationHelper.NotNull represents a contract, you can mark the called method with the ContractArgumentValidatorAttribute attribute. The Contract.EndContractBlock method call should be used to enable the tools to extract the proper specifications for document generation and static checking, as follows.
In addition to if-then-throw statements, the contract section of contract validator methods may contain calls to other contract validator methods. However, no other contracts (such as Contract.Requires, or Contract.Ensures) are allowed. Code that follows the Contract.EndContractBlock call is ignored by all contract tools.
The following example shows a range argument validator written in terms of an existing NotNull validator method.
From a specification point of view, the Execute method has the following three contracts:
Contract.Requires<ArgumentNullException>(data != null); Contract.Requires<ArgumentOutOfRangeException>(position >= 0); Contract.Requires<ArgumentOutOfRangeException>(position < data.Length);
In standard methods, calls to contract validator methods can be freely mixed with other contracts such as Contract.Ensures or Contract.Requires.
Available since 8
.NET Framework
Available since 4.5
Portable Class Library
Supported in: portable .NET platforms
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.



