Using WPF Validation rules and the disabling of a ‘Save’ button
Here is the complete sample what you need. http://codeblitz.wordpress.com/2009/05/08/wpf-validation-made-easy-with-idataerrorinfo/ https://skydrive.live.com/?cid=2c6600f1c1d5e3be&id=2C6600F1C1D5E3BE%21203