BCGSuite for MFC
BOOL CBCGPComboBox::SetImageList ( UINT  nImageListResID,
int  cxIcon = 16,
int  nVertMargin = 2,
BOOL  bAutoScale = FALSE,
BOOL  bDisplayIconLeftOfEditBox = FALSE 

Sets image list.

nImageListResIDIdentifier for the image list resource.
cxIconThe icon width.
nVertMarginThe icon vertical margin.
bAutoScaleTRUE to automatically scale according to DPI.
bDisplayIconLeftOfEditBoxIf this parameter is TRUE and selected combobox item has icon, the icon will be displayed on left side (CBS_DROPDOWN style).
TRUE if it succeeds, FALSE if it fails.