[Wissensdurst]

Dear Sir,

When I tried the operation described in the section "Selecting a record" on pp. 442 and 443 of your book, I got the following exception message from the browser:

"Invalid postback or callback argument. Event validation is enabled using <pages enableEventValidation="true"/> in configuration or <%@ Page EnableEventValidation="true" %> in a page. For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them. If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation."

This message appeared when I clicked on a Select button.

Could you please explain what is going on here and what should be done to avoid it?

Thank you for your trouble.

Eric

[Wissensdurst]

Sorry, Folks.

I have figured out the cause of the problem. In Page_Load I had the data source refreshed, even on postbacks.

Eric