by Simon Price (36 Submissions)
Category: Graphics
Compatability: Visual Basic 3.0
Difficulty: Beginner
Date Added: Wed 3rd February 2021
Rating: 
(8 Votes)
Convert any color format (hex, long, rgb) to any other color format. There may be other examples of this on VBC, but I checked them and they do not use the same algorithm. This is not the fastest way to convert colors, but it is simple and reliable.
VBcoders' *** COLOR CONVERSTION FUNCTIONS ***
' this is the main function, all the other converstion functions play off this 1
' accepted input hex formats: &H######, ######, #*****
' NOT: &H#***** !!! (i hope no1 would use that anyway)
Public Sub Hex2RGB(strHexColor As String, r As Byte, g As Byte, b As Byte)
Dim HexColor As String
Dim i As Byte
On Error Resume Next
' make sure the string is 6 characters long
' (it may have been given in &H###### format, we want ######)
strHexColor = Right((strHexColor), 6)
' however, it may also have been given as or #***** format, so add 0's in front
For i = 1 To (6 - Len(strHexColor))
HexColor = HexColor & "0"
Next
HexColor = HexColor & strHexColor
' convert each set of 2 characters into bytes, using vb's cbyte function
r = CByte("&H" & Right$(HexColor, 2))
g = CByte("&H" & Mid$(HexColor, 3, 2))
b = CByte("&H" & Left$(HexColor, 2))
End Sub
Public Function RGB2Hex(r As Byte, g As Byte, b As Byte) As String
On Error Resume Next
' convert to long using vb's rgb function, then use the long2rgb function
RGB2Hex = Long2Hex(RGB(r, g, b))
End Function
Public Sub Long2RGB(LongColor As Long, r As Byte, g As Byte, b As Byte)
On Error Resume Next
' convert to hex using vb's hex function, then use the hex2rgb function
Hex2RGB (Hex(LongColor))
End Sub
Public Function RGB2Long(r As Byte, g As Byte, b As Byte) As Long
On Error Resume Next
' use vb's rgb function
RGB2Long = RGB(r, g, b)
End Function
Public Function Long2Hex(LongColor As Long) As String
On Error Resume Next
' use vb's hex function
Long2Hex = Hex(LongColor)
End Function
Public Function Hex2Long(strHexColor As String) As Long
Dim r As Byte
Dim g As Byte
Dim b As Byte
On Error Resume Next
' use the hex2rgb function to get the red green and blue bytes
Hex2RGB strHexColor, r, g, b
' convert to long using vb's rgb function
Hex2Long = RGB(r, g, b)
End Function
