I was trying to incrementally change the background color of a cell to black, and I found that the Range.Interior.Color method returns a Long which is seemingly arbitrary. Looking at the documentation on MSDN, there is nearly nothing about what this number represents. Is there a way to return the RGB value from this long. I effectively need the opposite of the RGB(red, green, blue) function.
That "arbitrary" number is a mathematical combination of the RGB values (B*256^2 + G*256 + R) and a conversion of the hex color value to a decimal number (base 16 to base 10), depending on which way you want to look at it. Just different bases. Below is the method I use in the XLAM addin file I wrote for Excel. This method has come in handy many times. I have included the documentation in my addin file.
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' Function Color
' Purpose Determine the Background Color Of a Cell
' @Param rng Range to Determine Background Color of
' @Param formatType Default Value = 0
' 0 Integer
' 1 Hex
' 2 RGB
' 3 Excel Color Index
' Usage Color(A1) --> 9507341
' Color(A1, 0) --> 9507341
' Color(A1, 1) --> 91120D
' Color(A1, 2) --> 13, 18, 145
' Color(A1, 3) --> 6
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Function Color(rng As Range, Optional formatType As Integer = 0) As Variant
Dim colorVal As Variant
colorVal = Cells(rng.Row, rng.Column).Interior.Color
Select Case formatType
Case 1
Color = Hex(colorVal)
Case 2
Color = (colorVal Mod 256) & ", " & ((colorVal \ 256) Mod 256) & ", " & (colorVal \ 65536)
Case 3
Color = Cells(rng.Row, rng.Column).Interior.ColorIndex
Case Else
Color = colorVal
End Select
End Function