IProgressIndicator.Progress Property  
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Loading progress value from 0 (just started) to 1 (complete)
public:
 property float Progress {  void set(float value); };public float Progress { set; }member this.Progress : singlePublic Property Progress As Single