MSDN
DblClick Event

Occurs when the user presses and releases a mouse button and then presses and releases it again over an object.

For a form, the DblClick event occurs when the user double-clicks a disabled control or a blank area of a form. For a control, it occurs when the user:

Double-clicks a control with the left mouse button.

Double-clicks an item in a ComboBox control whose Style property is set to 1 (Simple) or in a FileListBox, ListBox, DataCombo, or DataList control.
Syntax

Private Sub Form_DblClick ( )

Private Sub object_DblClick (index As Integer)

...etc...

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Напр., SENDKEYS {ENTER}