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c#asp.netviewstate

How to get the value of built, encoded ViewState?

I need to grab the base64-encoded representation of the ViewState. Obviously, this would not be available until fairly late in the request lifecycle, which is OK.

For example, if the output of the page includes:

<input type="hidden" name="__VIEWSTATE" 
  id="__VIEWSTATE" value="/wEPDwUJODU0Njc5MD...==" />

I need a way on the server-side to get the value "/wEPDwUJODU0Njc5MD...=="

To clarify, I need this value when the page is being rendered, not on PostBack. e.g. I need to know the ViewState value that is being sent to the client, not the ViewState I'm getting back from them.

Solution

  • Rex, I suspect a good place to start looking is solutions that compress the ViewState -- they're grabbing ViewState on the server before it's sent down to the client and gzipping it. That's exactly where you want to be.