<Window.CommandBindings>

        <CommandBinding Command="Close" Executed="CloseCommand" />

        <CommandBinding Command="Save" Executed="SaveCommand"  CanExecute="SaveCanExecute" />

</Window.CommandBindings>

 <MenuItem Header="File">

                <MenuItem Header="Copy" Command="Copy" />

                <MenuItem Header="Paste" Command="Paste" />

                <MenuItem Header="Cut" Command="Cut" />

                <Separator></Separator>

                <MenuItem Header="Save" Command="Save" />

                <MenuItem Header="Close" Command="Close" />

</MenuItem>

<ToolBar Grid.Row="">

            <Button Command="Copy">

                <Image Source="/Images/Copy16x16.png" />

             </Button>

            <Button Command="Paste">

                <Image Source="/Images/Paste16x16.png" />

            </Button>

            <Button Command="Cut">

                <Image Source="/Images/Cut16x16.png" />

            </Button>

            <Button Command="Save">

                <Image Source="/Images/Save16x16.png" />

            </Button>

            <Button Command="Close">

                <Image Source="/Images/Close16x16.png" />

            </Button>

</ToolBar>

 <TextBox Grid.Row="" AcceptsReturn="True" TextChanged="TextBox_TextChanged" />

public partial class MainWindow : Window

{

    private bool isDirty = false;

    public MainWindow()

    {

        InitializeComponent();

    }

    private void CloseCommand(object sender, ExecutedRoutedEventArgs e)

    {

        MessageBox.Show("CloseCommand triggered with " + e.Source);

        App.Current.Shutdown();

    }

    private void SaveCommand(object sender, ExecutedRoutedEventArgs e)

    {

        MessageBox.Show("SaveCommand triggered with " + e.Source);

        isDirty = false;

    }

    private void SaveCanExecute(object sender, CanExecuteRoutedEventArgs e)

    {

        e.CanExecute = isDirty;

    }

    private void TextBox_TextChanged(object sender, TextChangedEventArgs e)

    {

        isDirty = true;

    }

}