Silverlight Togglebutton Set IsPressed state

Hello I have a Toggle button in Silverlight.

I want to set its state to "pressed".

First I tried :

  btButton.IsPressed = true

But that does not work (readonly).

Then I tried :

btButton.SetValue(ToggleB开发者_如何转开发utton.IsPressedProperty, true);

Which also does not work. How do I accomplish this ? I'd assume it would not be that hard...

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Use IsChecked. IsPressed tells you whether the mouse or space bar is currently pressing the button. IsChecked tells you how the button is toggled.

 btButton.IsChecked = true;