MVCContrib grid - sorting and paging

Every example I've run across demonstrating paging and sorting assume that the controller action that populates the grid does a getAll开发者_开发技巧 on the datasource. However in my application I am calling a web service that performs a search based on some form criteria passed in. When the pager or sort calls the action it sends nulls for all of the form data, thus breaking the result set that I originally had.

How do I implement paging and sorting without calling back to the web service again?

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instead,you can save the search criteria in session variable