How to create a model pop control type of future in C#.net?

hi developers,
here is my need: 
   i want to add a class , when ever i click on the button one popup should come with  


 Class :---------
 OK     CANCEL 
Like above.
after enter class and click on OK button that should be  close and added to data gridview.
Thank u
Best Regards,
Thiru


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