ListGetDifferent.cfm

<cffunction name="ListGetDifferent" output="yes">
    <cfargument name="mainList" required="Yes" />
    <cfargument name="compareList" required="Yes" />
    <cfargument name="CompareType" required="Yes" default="Same" />
    <cfset ReturnList = "" />
    <cfif CompareType EQ "Same">
        <cfloop list="#mainList#" index="i">
            <cfif ListFindNoCase(compareList,i)>
                <cfset ReturnList = ListAppend(ReturnList,i) />
            </cfif>
        </cfloop>
    <cfelse>
        <cfloop list="#mainList#" index="i">
            <cfif NOT ListFindNoCase(compareList,i)>
                <cfset ReturnList = ListAppend(ReturnList,i) />
            </cfif>
        </cfloop>
    </cfif>
    <cfreturn ReturnList />
</cffunction>

Usage of UDF is as follow.

ListGetDifferent("1,2,3,4,5", "1,3,5", "Same")

ListGetDifferent("1,2,3,4,5", "1,3,5", Differ")#