[quote user="m gao"]wdexpress does NOT support 'rebuild' option[/quote]
Viz Studio has an internal make file. The build process checks dependencies to find what must be rebuilt. If a dependency is out-of-date or missing, then it is rebuilt. A simple way to force a rebuild is to delete all dependencies.
As far as I can see, for the WPFSample example, there is only one dependency: WPFSample.dll. If you delete that file, then Viz Studio will rebuild it.
Please refer to my earlier post: I am able to build and run that example.