ICommand Interface

Definition

Namespace:

System.Windows.Input

Assembly:

System.ObjectModel.dll

Defines a command.

public interface class ICommand

[System.ComponentModel.TypeConverter("System.Windows.Input.CommandConverter, PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, Custom=null")]
public interface ICommand

[<System.ComponentModel.TypeConverter("System.Windows.Input.CommandConverter, PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, Custom=null")>]
type ICommand = interface

Public Interface ICommand

Derived

Microsoft.Windows.Input.IPreviewCommand

System.Windows.Input.RoutedCommand

Attributes

TypeConverterAttribute

Remarks

RoutedCommand and RoutedUICommand are two implementations of the ICommand interface in Windows Presentation Foundation (WPF).

ICommand in Windows Runtime apps

The ICommand interface is the code contract for commands that are written in .NET for Windows Runtime apps. These commands provide the commanding behavior for UI elements such as a Windows Runtime XAML Button and in particular an AppBarButton. If you're defining commands for Windows Runtime apps, you use basically the same techniques you'd use for defining commands for a .NET app. Implement the command by defining a class that implements ICommand and specifically implement the Execute method.

XAML for Windows Runtime does not support x:Static, so don't attempt to use the x:Static markup extension if the command is used from Windows Runtime XAML. Also, the Windows Runtime does not have any predefined command libraries, so the XAML syntax shown here doesn't really apply for the case where you're implementing the interface and defining the command for Windows Runtime usage.

XAML attribute usage

<object-property="predefined-command-name"/>
-or-
<object-property="predefined-class-name.predefined-command-name"/>
-or-
<object-property="{custom-class-name.custom-command-name}"/>

XAML values

predefined-class-name
One of the predefined command classes.

predefined-command-name
One of the predefined commands.

custom-class-name
A custom class that contains the custom command. Custom classes generally require an xlmns prefix mapping. For more information, see XAML Namespaces and Namespace Mapping for WPF XAML.

custom-command-name
A custom command.

Methods

CanExecute(Object)	Determines whether the command can execute in its current state.
Execute(Object)	Defines the method to be called when the command is invoked.

Events

CanExecuteChanged

Occurs when changes take place that affect whether or not the command should execute.