.NET Framework 4.6 and 4.5
Updates the DesiredSize of the image. This method is called by the parent UIElement and is the first pass of layout.
protected override Size MeasureOverride(
The image will always return its natural size, if it fits within the constraint. If not, it will return as large a size as it can.
Supported in: 4.6, 4.5, 4, 3.5, 3.0
.NET Framework Client Profile
Supported in: 4, 3.5 SP1