Isabelle,

>My problem is the following: I would like to validate what the user can enter when editing the order detail grid view. For now, some validations have been done in the Jump Start, but I have the following problem: When I enter a string (eg: "test") in the ProductId column of the grid for example, I get an exception because this value "test" cannot be converted in integer...

Rather than using a free-form text field for the product id, you can instead use a dropdown list in the grid to allow the user to select from a list of products. For details, see the MM .NET Dev Guide topic "Adding a DropDownList to the GridView".

Best Regards,