Specifies the color index.
Supported platforms: Windows only
Read-only: No
Type: acColor enum
The default color designation is acByLayer. Use a color index number from 0 to 256, or one of the constants listed here:
No additional remarks.
VBA:
Sub Example_ColorIndex()
    'This example draws a circle and
    'returns the closest color index.
    
    Dim cir As AcadCircle
    Dim pt(0 To 2) As Double
    Set cir = ThisDrawing.modelSpace.AddCircle(pt, 2)
    Dim col As AcadAcCmColor
    Set col = cir.TrueColor
    col.SetRGB 125, 175, 235
    cir.TrueColor = col
    ZoomAll
    
    Dim retCol As AcadAcCmColor
    Set retCol = cir.TrueColor
    
    If col.ColorMethod = AutoCAD.acColorMethodByRGB Then
        MsgBox "Closest ColorIndex=" & col.ColorIndex
    End If
End Sub
 
  Visual LISP:
(vl-load-com)
(defun c:Example_ColorIndex()
    ;;This example draws a circle and
    ;;returns the closest color index.
    (setq acadObj (vlax-get-acad-object)
          doc (vla-get-ActiveDocument acadObj))    
    (setq pt (vlax-3d-point 0 0 0))
    (setq modelSpace (vla-get-ModelSpace doc)
          cir (vla-AddCircle modelSpace pt 2)
          col (vla-get-TrueColor cir))
    (vla-SetRGB col 125 175 235)
    (vla-put-TrueColor cir col)
    (vla-ZoomAll acadObj)
    
    (setq retCol (vla-get-TrueColor cir))
    
    (if (= (vla-get-ColorMethod col) acColorMethodByRGB)
        (alert (strcat "Closest ColorIndex=" (itoa (vla-get-ColorIndex col))))
    )
)