?<Window x:Class="DTSample.BindingToCtrl"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:qq="clr-namespace:DTSample" 
    Title="DTSample" Height="300" Width="300" Loaded="Onload"
    >    
  <StackPanel>
      <!--,UpdateSourceTrigger= Explicit    LostFocus  PropertyChanged-->
      <TextBox x:Name="MyTextBox" Width="100" Height="50" Text="{Binding Path=Content}"></TextBox>      
      <TextBlock Text="{Binding ElementName=MyTextBox, Path=Text}" Width="300" Height="50"></TextBlock>
      <TextBlock x:Name="MyTextBlock" Text="{Binding Path=Content}" Width="300" Height="50"></TextBlock>
    
      <Button>lost focus</Button>
      <Button Click="OnClick">Update</Button>
    </StackPanel>
  
</Window>