如何暂停方法执行，并在客户端响应后恢复？

I have a mvc web application in where user send request to server. On execution of method DoSomething(int x) , a validation occurs. So i need to send back a response on the user asking for confirmation. If the user click Yes i should continue the execution of DoSomething(int x). If user response No i will stop for the user to do some changes and resubmit again. I have try to mimic my scenario in the code below: The idea is for you to understand the issue. Now the question: Is there a way to use thread? hint:If this was a windows form it is easy Showdialog will take care of it.I have a mvc web application in where user send