从XAML调用位于类中的事件或方法

 <Window x:Class=\"TestBed.TestWindow\"
    xmlns=\"http://schemas.microsoft.com/winfx/2006/xaml/presentation\"
    xmlns:x=\"http://schemas.microsoft.com/winfx/2006/xaml\"
    xmlns:i=\"clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity\"
    xmlns:cmd=\"clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras\">
    <Grid>
        <TextBox x:Name = \"MyTextBox\">
            <i:Interaction.Triggers>
                <i:EventTrigger EventName=\"TextChanged\">
                    <cmd:EventToCommand Command=\"{Binding TextChanged, Mode=OneWay}\"
                                        CommandParameter=\"{Binding Text, 
                                              ElementName=MyTextBox, Mode=OneWay}\"
                        MustToggleIsEnabledValue=\"True\" />
                </i:EventTrigger>
            </i:Interaction.Triggers>
        </TextBox>
    </Grid>
</Window>

public partial class TestWindow : Window
{
    public TestWindow()
    {
        this.TextChangedCommand = new RelayCommand<string>(
            (str) => TextChanged(str));

        InitializeComponent();
    }

    public RelayCommand<string> TextChangedCommand
    {
        get;
        private set;
    }

    public void TextChanged(string str)
    {
    }
}

public static class Commands
{
    public static RoutedCommand DoStuff = new RoutedCommand();
}

<Button x:Key=\"TheButton\" Content=\"Click\"
        Command=\"{x:Static local:Commands.DoStuff}\" />

<Grid>
    <Grid.CommandBindings>
        <CommandBinding Command=\"{x:Static local:Commands.DoStuff}\"
                        Executed=\"DoStuff_Executed\"
                        CanExecute=\"DoStuff_CanExecute\"/>
    </Grid.CommandBindings>
    <StaticResource ResourceKey=\"TheButton\"/>
</Grid>

private void DoStuff_Executed(object sender, ExecutedRoutedEventArgs e)
{
    // What happens if the command is executed, in this case the Button-click can
    // cause this to happen, you can also create KeyBindings which can execute
    // commands for example.
    MessageBox.Show(\"!\");
}
private void DoStuff_CanExecute(object sender, CanExecuteRoutedEventArgs e)
{
    e.CanExecute = true; //No condition: Command can always be executed

    // e.CanExecute = false causes the button to be disabled.
}