title: Change binding value, not binding itself
body: <p>I've got a WPF UserControl containing a DependencyProperty (MyProperty).</p>
  
  <p>The DependencyProperty is bound to a Property in the DataContext.</p>
  
  <p>Now in the UserControl I want to change the value of the bound property. But if I assign <code>MyProperty = NewValue</code> the Binding is lost and replaced by NewValue.</p>
  
  <p>What I want to achieve is change the DataContext-property the DependencyProperty is bound to.</p>
  
  <p>How do I achieve this instead of changing the binding?</p>
  
  <p>To clarify: using something like <code>MyTextBox.Text = "0";</code> I'll release the binding. How would I set Text, leave the binding intact so the property Text is bound to will change, too.</p>