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:

<cfscript>
/**
 * Generate random colors for cfcharts!
 * 
 * @param numToReturn 	 Number of colors to return. (Required)
 * @return Returns a string. 
 * @author Pablo Varando (&#119;&#101;&#98;&#109;&#97;&#115;&#116;&#101;&#114;&#64;&#101;&#97;&#115;&#121;&#99;&#102;&#109;&#46;&#99;&#111;&#109;) 
 * @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;
}
</cfscript>