StackPanel.ViewportWidth Property   
Definition
Important
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Gets a value that contains the horizontal size of the content's viewport.
public:
 property double ViewportWidth { double get(); };public double ViewportWidth { get; }member this.ViewportWidth : doublePublic ReadOnly Property ViewportWidth As DoubleProperty Value
The Double that represents the vertical size of the content's viewport. The default value is 0.0.
Implements
Remarks
The returned value is described in Device Independent Pixels.