ValidationSummary Control

In addition to identifying specific fields with data entry problems, it is often useful to provide users with a summary of validation problems on a form. You can use the ValidationSummary control to provide that summary information to users. The ValidationSummary control is used to display the ErrorMessage property values from validation controls on the page when controls being validated are invalid.

Using the ValidationSummary control can improve usability by minimizing distracting and confusing text and by drawing the user's attention to a single location. Displaying specific data validation problems next to each field can consume a lot of screen real estate. In addition, it can cause shifts in screen layout, which leads to confusion. Using a ValidationSummary control concentrates more verbose information in a single location. Good examples of this include placing asterisks or exclamation points next to fields with validation problems.