如何获取InputBinding-Command的发送者

Question

我有这个xaml代码:

<Window.InputBindings>
    <KeyBinding Command="{Binding Path=KeyEnterCommand}" Key="Enter" />
</Window.InputBindings>

这就是我的ViewModel中的代码:

    private RelayCommand _keyEnterCommand;

    public ICommand KeyEnterCommand
    {
        get
        {
            if (_keyEnterCommand == null)
            {
                _keyEnterCommand = new RelayCommand(param => ExecuteKeyEnterCommand());
            }

            return _keyEnterCommand;
        }
    }

    public void ExecuteKeyEnterCommand()
    {
        // Do magic
    }

现在是我的问题,我怎样才能得到这个命令的发件人？

Answer 1

如果"发送者"是指按下键时聚焦的元素,则可以将当前聚焦的元素作为参数传递给命令,如下所示:

<Window x:Class="MyWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        x:Name="root">
    <Window.InputBindings>
        <KeyBinding Command="{Binding Path=KeyEnterCommand}"
                    CommandParameter="{Binding ElementName=root, Path=(FocusManager.FocusedElement)}"
                    Key="Escape" />
    </Window.InputBindings>
...

private RelayCommand<object> _keyEnterCommand;

public ICommand KeyEnterCommand
{
    get
    {
        if (_keyEnterCommand == null)
        {
            _keyEnterCommand = new RelayCommand<object>(ExecuteKeyEnterCommand);
        }

        return _keyEnterCommand;
    }
}

public void ExecuteKeyEnterCommand(object sender)
{
    // Do magic
}