Show the 'Choose a Color' Common Dialog

Option Explicit
Private Declare Function ChooseColorA Lib "comdlg32.dll" (pChoosecolor As tChooseColor) As Long
Private Declare Function GetActiveWindow Lib "user32" () As Long

Private Type tChooseColor
lStructSize As Long
hwndOwner As Long
hInstance As Long
rgbResult As Long
lpCustColors As String
flags As Long
lCustData As Long
lpfnHook As Long
lpTemplateName As String
End Type

'Purpose : Shows the Choose Color Dialog
'Inputs : N/A
'Outputs : Returns -1 if the user pressed cancel, else returns the selected color


Function ShowColor() As Long
Dim tColor As tChooseColor
Dim Custcolor(16) As Long
Dim lReturn As Long, lThisColor As Long
Dim abytCustomColors(0 To 16 * 4 - 1) As Byte

For lThisColor = LBound(abytCustomColors) To UBound(abytCustomColors)
abytCustomColors(lThisColor) = 0
Next

tColor.lStructSize = Len(tColor)
tColor.hwndOwner = GetActiveWindow 'or Me.hwnd in VB
tColor.hInstance = 1 'or App.hInstance in VB
'Convert the custom colors to Unicode
tColor.lpCustColors = StrConv(abytCustomColors, vbUnicode)
tColor.flags = 0

'Show the dialog
If ChooseColorA(tColor) <> 0 Then
ShowColor = tColor.rgbResult
Else
ShowColor = -1
End If
End Function

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