Dim arColors As KnownColor() = [Enum].GetValues(GetType(KnownColor))

Private Function IsKnownColor(ByVal c As Color) As Boolean
	Dim arColors As KnownColor() = [Enum].GetValues(GetType(KnownColor))
	Dim colorTable As New Hashtable(arColors.Length)
	For Each kc As KnownColor In arColors
		If Not colorTable.ContainsKey(Color.FromKnownColor(kc).ToArgb) Then
			colorTable.Add(Color.FromKnownColor(kc).ToArgb, kc.ToString)
		End If
	Next
	Return colorTable.ContainsKey(c.ToArgb)
End Function