property MaskEdit.SelStart as Long
Returns or sets the starting point of text selected.

TypeDescription
Long A long expression that indicates the starting point of the text selected. 
The SelStart property returns or sets the starting point of text selected; indicates the position of the insertion point if no text is selected. The SelEnd property returns or sets the ending point of the text selected. Use the Select method to select a part of the control's text. The SelectGotFocus property indicates what the control should select once the control gets the focus.