thermoluminescence dating of ocean sediments - Aspx validating
This kind of situation is handled using validation groups.
To create a validation group, you should put the input controls and the validation controls into the same logical group by setting their Validation Group property.
After all of the validation controls have been called, a property on the page is set indicating whether any validation check has failed.
Validation controls can be organized into groups that enable you to selectively enable or disable validation for related controls on a page.
In addition, validation controls allow you to customize how error information is displayed to the user.