title: Concept of "UpdateSourceTrigger" Property, How to use it in WPF?
body: <p>I have a TextBlock, binded with an Object and when i update property of object its not refleting on UI, Why ?</p>
  
  <p>Code:</p>
  
  <h2>In Windows1.xaml</h2>
  
  <pre><code>&lt;TextBlock Name="txtName" Text="{Binding Name, UpdateSourceTrigger=PropertyChanged}" Width="100" Height="20" Margin="12,23,166,218" /&gt;
  </code></pre>
  
  <h2>and In Windows.xaml.cs</h2>
  
  <pre><code>public partial class Window1 : Window
  {
      Employee obj ;
      public Window1()
      {            
          InitializeComponent();
          obj = new Employee();
          obj.Name = "First";
          txtName.DataContext = obj;
      }
  
      private void btnUpdate_Click(object sender, RoutedEventArgs e)
      {
          obj.Name = "changed";            
      }
  }
  public class Employee : INotifyPropertyChanged
  {
      public event PropertyChangedEventHandler PropertyChanged;
      private string _name;
      public string Name
      {
          set 
          {
              this._name = value;
              OnPropertyChanged(Name);
          }
          get { return this._name; }
      }
  
      protected void OnPropertyChanged(string name)
      {
  
          PropertyChangedEventHandler handler = PropertyChanged;
  
          if (handler != null)
          {
  
              handler(this, new PropertyChangedEventArgs(name));
  
          }
  
      }        
  }
  </code></pre>