Option Explicit
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' Copyright ©1996-2011 VBnet/Randy Birch, All Rights Reserved.
' Some pages may also contain other copyrights by the author.
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' Distribution: You can freely use this code in your own
' applications, but you may not reproduce
' or publish this code on any web site,
' online service, or distribute as source
' on any media without express permission.
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Private Declare Function OleTranslateColor Lib "olepro32.dll" _
(ByVal OLE_COLOR As Long, _
ByVal HPALETTE As Long, _
pccolorref As Long) As Long
Private Sub Form_Load()
With Command1
.Caption = "Select Colour"
End With
With Label1
.AutoSize = True
.Caption = ""
.WordWrap = True
.Move 200, 200, Form1.ScaleWidth - 400
.Caption = "Select any colour from the common " & _
"colour dialog. This label background " & _
"and left picturebox will take on the " & _
"selected colour, while the label's text " & _
"and right picturebox will display " & _
"the inverse of the selection."
.AutoSize = True
End With
End Sub
Private Sub Command1_Click()
With CommonDialog1
.ShowColor
Label1.BackColor = .Color
Label1.ForeColor = InverseRGB(.Color)
Picture1.BackColor = .Color
Picture2.BackColor = InverseRGB(.Color)
End With
End Sub
Public Function InverseRGB(ByVal col As Long) As Long
Const Inverse As Long = &HFFFFFF
InverseRGB = GetClrrefFromOLEColour(col) Xor Inverse
End Function
Private Function GetClrrefFromOLEColour(ByVal dwOleColour As Long) As Long
'pass a colour, and return the colour
'with the system bit stripped if present
OleTranslateColor dwOleColour, 0, GetClrrefFromOLEColour
End Function |
Here's
a quick routine that when passed a RGB value or a OLE system colour will
return the inverse of the colour passed. The method uses OleTranslateColor() to convert to RGB the colour passed, if required,
then flips the colour by OR'ing it with &HFFFFFF (decimal 16777215).
The result is the bitwise opposite of the colour passed which could be
used to provide a contrasting background for a given text colour, as
shown.
