the general question is "Is anyone have an idea on how to implement a load button which will make the viewstate to load with a specific file ?"

[u]details :</u>
I have some web forms which allow to select data to make request on Reporting Services.

Now i have to add a functionnality to these web forms. On every web forms (which are not using the same controls), i must provide a way to save the data selected. Of course, i want to use the same functionnality to save the state of each web forms.

So my idea was to use the viewstate, i override "LoadPageStateFromPersistenceMedium" and "SavePageStateToPersistenceMedium" to store the viewState into a file, so when the user want to save is request, i store the file corresponding to the viewstate into another directory and when the user want to load the latest request, i want to use this file to load the viewstate.

everything is working, expect that i can't figure out how to load correctly this viewstate. I mean i don't know how to implement a load button which will load the file ... because the method which load the viewstate is called before my "LOAD" button method, i can only see my data when i click a second time on it ...

SO Is anyone have an idea on how to implement a load button which will make the viewstate to load a specific file ?