Visual Basic Reference
Returns or sets an expression that stores any extra data needed for your program. Unlike other properties, the value of the Tag property isn't used by Visual Basic; you can use this property to identify objects.
object.Tag [= expression]
The Tag property syntax has these parts:
|object||An object expression that evaluates to an object in the Applies To list.|
|expression||A string expression identifying the object. The default is a zero-length string ("").|
You can use this property to assign an identification string to an object without affecting any of its other property settings or causing side effects. The Tag property is useful when you need to check the identity of a control or MDIForm object that is passed as a variable to a procedure.
Tip When you create a new instance of a form, assign a unique value to the Tag property.