CFLib.org – Common Function Library Project

Description:
This UDF will allow you to generate random colors that you can use with your charts. Pass in a numbr of colors and it will randomly generate as many colors are you requested in a comma delimited list to pass into a cfchartseries colorlist.

Return Values:
Returns a string.

Example:

<cfquery name="qGetTutorialStats" datasource="#application.dsn#">
        select    tutorialID, title, views
        from    paidTutorials
        where    authorID = #val(session.authorID)#
    </cfquery>

    <!--- my stats --->
    <cfchart format="flash" title="Tutorial Views" chartwidth="700" chartheight="400" show3d="yes">
        <cfchartseries type="bar" colorlist="#returnRandomHEXColors(qGetTutorialStats.recordCount)#">
            <cfloop query="qGetTutorialStats">
                <cfchartdata item="#title#" value="#views#" />
            </cfloop>
        </cfchartseries>
    </cfchart>

Parameters:

Full UDF Source:

/**
 * Generate random colors for cfcharts!
 * 
 * @param numToReturn      Number of colors to return. (Required)
 * @return Returns a string. 
 * @author Pablo Varando (webmaster@easycfm.com) 
 * @version 0, June 12, 2009 
 */
function returnRandomHEXColors(numToReturn) {
    var returnList = ""; // define a clear var to return in the end with a list of colors
    var colorTable = "A,B,C,D,E,F,0,1,2,3,4,5,6,7,8,9"; // define all possible characters in hex colors
    var i = "";
    var tRandomColor = "";
    // loop through and generate as many colors as defined by the request
    for (i=1; i LTE val(numToReturn); i=i+1){
        // clear the color list
        tRandomColor = "";
        for(c=1; c lte 6; c=c+1){
            // generate a random (6) character hex code
            tRandomColor = tRandomColor & listGetAt(colorTable, randRange(1, listLen(colorTable)));
        }
        // append it to the list to return in the end
        returnList = listAppend(returnList, tRandomColor);
    
    }
    // return the list of random colors
    return returnList;
}