minimize the window on cross button click event just like skype or other VOIP apps in WPF

I have to create a WPF app where user click on cross button its should minimize the app on task bar instead of closing , its same as skype perform.

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525" Closing="Window_Closing">
   
     
   

 private void Window_Closing(object sender, System.ComponentModel.CancelEventArgs e)
        {
            WindowState = WindowState.Minimized;
            e.Cancel = true;
        }