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Each time you supply a value in a control, sends an asynchronous request to the server to vaiveidate validate the data. This means users do not have to complete the entire form before discovering data was entered incorrectly—try to type letters in a number control, for example, and you’ll immediately see an error message. And, if your form includes rules that are associated with a particular control, the server will apply these rules as soon as users enter data in the control. For example, perhaps your form has a rule that enables the “Guest Name” control when you select the Yes radio button in the “Are You Bringing a Guest?” control. In this case the Guest Name control will be enabled immediately--while you are still completing the form!
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