The exception that is thrown when a requested method or operation is not implemented.
Assembly: mscorlib (in mscorlib.dll)
Initializes a new instance of theclass with default properties.
Initializes a new instance of theclass with serialized data.
Initializes a new instance of theclass with a specified error message.
Initializes a new instance of theclass with a specified error message and a reference to the inner exception that is the cause of this exception.
Gets a collection of key/value pairs that provide additional user-defined information about the exception.(Inherited from Exception.)
Gets or sets a link to the help file associated with this exception.(Inherited from Exception.)
Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception.(Inherited from Exception.)
Gets a message that describes the current exception.(Inherited from Exception.)
Gets or sets the name of the application or the object that causes the error.(Inherited from Exception.)
Gets a string representation of the immediate frames on the call stack.(Inherited from Exception.)
Gets the method that throws the current exception.(Inherited from Exception.)
Determines whether the specified object is equal to the current object.(Inherited from Object.)
Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)
Serves as the default hash function. (Inherited from Object.)
Gets the runtime type of the current instance.(Inherited from Exception.)
Creates and returns a string representation of the current exception.(Inherited from Exception.)
Theexception is thrown when a particular method, get accessor, or set accessor is present as a member of a type but is not implemented.
You might choose to throw aexception in properties or methods in your own types when the that member is still in development and will only later be implemented in production code. In other words, a exception should be synonymous with "still in development."
Theexception indicates that the method or property that you are attempting to invoke has no implementation and therefore provides no functionality. As a result, you should not handle this error in a try/catch block. Instead, you should remove the member invocation from your code. You can include a call to the member when it is implemented in the production version of a library.
In some cases, aexception may not be used to indicate functionality that is still in development in a pre-production library. However, this still indicates that the functionality is unavailable, and you should remove the member invocation from your code.
The .NET Framework also includes two other exception types, NotSupportedException and PlatformNotSupportedException, that indicate that no implementation exists for a particular member of a type. You should use throw one of these instead of a exception under the following conditions.
- PlatformNotSupportedException exception
If you've designed a type with one or more members that are available on some platforms or in some versions but not on others, you can throw this exception on platforms on which the functionality is not supported.
- NotSupportedException exception
Throw a NotSupportedException exception if the implementation of an interface member or an override to an abstract base class method is not possible. For example, the Convert.ToInt32(DateTime) method throws a NotSupportedException exception because no meaningful conversion between a date and time and a 32-bit signed integer exists. The method must be present in this case because the Convert class implements the IConvertible interface.
You should also throw a NotSupportedException exception if you've implemented an abstract base class and add a new member to it that must be overridden by derived classes. In that case, making the member abstract causes existing subclasses to fail to load.
The following example throws this exception for a method that has not been developed.
Available since 4.5
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
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.