title: Raise event if any control has been changed WPF
body: <p>I want make validation in my WPF application. And the approach I want to use is I want to take custom action if any value of my controls has been changed.</p>
  
  <p>How I can do that suppose I have control like this</p>
  
  <pre><code>&lt;TextBox x:Name="TextBox1" Text="{Binding Path=Box1,UpdateSourceTrigger=PropertyChanged}" /&gt;
  &lt;TextBox x:Name="TextBox2" Text="{Binding Path=Box2,UpdateSourceTrigger=PropertyChanged}" /&gt;
  </code></pre>
  
  <p>And If user change the value one of that control I want to create custom action for example <strong>(For my thinking )</strong></p>
  
  <pre><code>private void Window_Controls_Property_Changed(object sender,RoutedEventArgs e){
    if(((Control)sender)=="TextBox1")
      MessageBox.Show("Show message here of validation some control","Attention",MessageBoxButton.OK);
  }
  </code></pre>
  
  <p>I'm still confusing combine the <code>INotifyPropertyChanged</code> or <code>ValidationRule</code> with displaying error what I want with MessageBox. I'm still newbie using this kind of features.</p>
  
  <p>I have read many articles about <code>INotifyPropertyChanged</code> or <code>ValidationRule</code> but I'm still don't know how to get the custom action like I said before. And the custom validation may use another textbpx value to validate with the other textbox.</p>
  
  <p>Any helps?.. </p>