Use the AssociatedControlID property to associate a Label control with another server control on a Web form. When a Label control is associated with another server control, its attributes can be used to extend the functionality of the associated control. You can use the Label control as a caption for another control, or you can set the tab index or hot key for an associated control.
When the AssociatedControlID property is set, the Label control renders as an HTML label element, with the for attribute set to the ID property of the associated control. You can set other attributes of the label element using the Label properties. For example, you can use the Text and AccessKey properties to provide the caption and hot key for an associated control.
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Lalit Dwivedi
Cybage, pune