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custom property binding and override DependencyObject.GetValue

Posted By:      Posted Date: May 22, 2011    Points: 0   Category :JavaScript/VBScript


I am looking for a way to override DependencyObject.GetValue. The reason is:

  1. the standard implementation of GetValue in .NET framework library tightly coupled with ActivityBind, it does not work with any other binding implementation;
  2. ActivityBind is not good enough for my project;
  3. ActivityBind is sealed, I cannot derive my own binding from it;
  4. So I have to completely bypass ActivityBind and somehow let GetValue call my custom property binding mechanism.

The only extension point of GetValue I found is the delegate GetValueOverride. But sadly, this GetValueOverride takes only 1 parameter which is the DependencyObject the delegate is called about, that means the call back function will not know what property it is called about.

Does anybody have any other idea about customizing property binding and/or DependencyObject.GetValue?

I do have a feeling that the implementation of property binding in the framework need second thought, currently they are so hard to be extended.



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