Determines the number of elements in a list.

Integer; the number of elements in a list.

List functions

ListLen(list [, delimiters ])

ListAppend, ListDeleteAt, ListInsertAt, ListPrepend; "Lists" in Chapter 3, "Using ColdFusion Variables," in ColdFusion MX Developer's Guide

ColdFusion ignores empty list elements; thus, the list "a,b,c,,,d" has four elements.

Here are some examples of ListLen processing:

ListLen('a,b, c,,,d')

ListLen('a,b, c,,,d',',')

ListLen('elem_1___elem_2___elem_3')

ListLen('elem*1***elem*2***elem*3')

ListLen('elem_1___elem_2___elem_3','_')

<h3>ListLen Example</h3>
<!--- Find a list of users who wrote messages --->
<cfquery name = "GetMessageUser" datasource = "cfdocexamples">
   SELECT Username, Subject, Posted
   FROM  Messages
</cfquery>
<cfset temp = ValueList(GetMessageUser.Username)>
<!--- loop through the list and show it with ListGetAt --->
<h3>This is a list of usernames who have posted messages
<cfoutput>#ListLen(temp)#</cfoutput> users.</h3>
<ul>
<cfloop From = "1" TO = "#ListLen(temp)#" INDEX = "Counter">
   <cfoutput><li>Username #Counter#: 
    #ListGetAt(temp, Counter)#</cfoutput>
</cfloop>
</ul>