Web Development

'-------------------------------------------------------------------------------
'-------------------------------------------------------------------------------
function GetColorValue(sColor, nShade)
    Replace sColor, "#", ""
    Dim nVal: nVal = 0
    select case nShade
        case 0 nVal = CLng("&H" & (Mid(1, 2)))    ' red
        case 1 nVal = CLng("&H" & (Mid(3, 2)))    ' green
        case 2 nVal = CLng("&H" & (Mid(5, 2)))    ' blue
    end select
    GetColorValue = nVal
end function

'-------------------------------------------------------------------------------
' Extracts the color value from the string that represents the backgorund color.
' It's assumed that the color will ALWAYS be in the standard hex notation of    
' #RRGGBB.  jms - 07May2007                                                     
'-------------------------------------------------------------------------------
function GetColorValue(sColor, nShade)
    Dim nVal: nVal = 0
    select case nShade
        case 0 nVal = CLng("&H" & (Mid(sColor, 2, 2)))  ' red
        case 1 nVal = CLng("&H" & (Mid(sColor, 4, 2)))  ' green
        case 2 nVal = CLng("&H" & (Mid(sColor, 6, 2)))  ' blue
        case else nVal = 255
    end select
    GetColorValue = nVal
end function

'-------------------------------------------------------------------------------
' Determines the best choice of text color based on the background color. The   
' two possible resulting values are black text or white text.  jms - 07MAY2007  
'-------------------------------------------------------------------------------
function BestFontColor(sBkColor)
    if sBkColor(1) <> "#" OR Len(sBkColor) < 7 then
        BestFontColor = "#000000"
        exit function
    end if
    Dim nRed:   nRed   = GetColorValue(sBkColor, 0)
    Dim nGreen: nGreen = GetColorValue(sBkColor, 1)
    Dim nBlue:  nBlue  = GetColorValue(sBkColor, 2)
    
    Dim nThreshold: nThreshold = 105
    Dim bgDelta: bgDelta = int((nRed * 0.299) + (nGreen * 0.587) + (nBlue * 0.114))
    if 255 - bgDelta < nThreshold then
        BestFontColor = "#000000"
    else
        BestFontColor = "#FFFFFF"
    end if
end function