How to delete "System Reserved Partition" for win7 through programming?

Question

I deleted the partition manually.

1. diskpart---> set active partition to c:;
2. bcdboot c:\windows /s c:

3. on boot(by start from dvdrom or Udisk), diskpart----> delete partition override

   But in my experiences, the 3rd step must be executed on boot. If the system is already startup, "delete partition override" will fail with the cause "can't delete system partition".

   Then my problem maybe has becomed: is there a way to manually delete the partition when the user is logged in win7, otherwise can the VDS api solve the problem?

   Thanks in advance, Siguang Zhang