Validation of multiple dropdowns in .Net4

[Alex Robinson]

This is making me crazy! I have validated hundreds of forms during my career, but this won't work no matter what I try!

I have 5 dropdownlists populated via sql database that only appear in a GridView row, when it is selected. On each I have added <asp:ListItem Text="Select.." Value="0" /> and AppendDataBoundItems="true".

I also have events on SelectedIndexChanged and DataBinding therefore during validation what is happening is if one dropdown has not been selected, I lose the values selected from all the others when I prompt the user to select a value.

I have posted code in a few Microsoft forums and been given a lot of advice, all of which I have tried and none have worked.

I would like to use the built-in validation, but I have also tried client side with JavaScript. I have tried saving the correct values to Session["variable"] but each time the user (me) selects a valid value from a dropdown, the page performs a postback and loses the values from the others.

I am desperate as tomorrow is the deadline and this is the only part of the Web App not working! Please help!

[Frinavale]

Wait, why are you losing the other selected values??
These should be stored in ViewState...

Why are you having this problem?

Edit: oh it's because of the binding.

I use the Page PreRender event to reset any values that need to be set....the Page PreRender is the last time you have access to controls before they are rendered into HTML and sent to the browser. It occurs after all other events have happened so you know that whatever you do here will not be reset.