From Xojo Documentation

Property (As Integer )
aBevelButton.IconDx = newIntegerValue
IntegerValue = aBevelButton.IconDx

Supported for all project types and targets.

The distance (in points) from flush left or right, depending on alignment. If center alignment is chosen, IconDx does nothing.

Sample Code

The following code places an icon in the bevelbutton, aligns it, and specifies the placement of the caption. The graphic, "DatabaseQueryIcon," has been added to the Project Editor.

Me.Icon = DatabaseQueryIcon
Me.IconAlign = 6
Me.CaptionAlign = 0
Me.CaptionPlacement = 2
Me.IconDx = 2
Me.IconDy = 1