Center in Form Commands (Format Menu)
From Microsoft Visual Basic User Interface
Center in Form Commands (Format Menu)
Centers selected objects on the central axes of the form.
Horizontally
Aligns the middles of the selected objects to a horizontal line in the middle of the form.
Toolbar shortcut: 
.
Vertically
Aligns the centers of the selected objects to a vertical line in the center of the form.
Toolbar shortcut: 
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