User Guide

728 Chapter 3: ColdFusion Functions
ListLen
Description
Determines the number of elements in a list.
Integer; the number of elements in a list.
Category
List functions
Function syntax
ListLen(list [, delimiters ])
See also
ListAppend
, ListDeleteAt, ListInsertAt, ListPrepend; “Lists” in Chapter 3, “Using
ColdFusion Variables,” in ColdFusion MX Developer’s Guide
Parameters
Usage
ColdFusion ignores empty list elements; thus, the list "a,b,c,,,d" has four elements.
Here are some examples of ListLen processing:
Example
<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
Parameter Description
list A list or a variable that contains one.
delimiters A string or a variable that contains one. Character(s) that separate list elements.
The default value is comma.
If this parameter contains more than one character, ColdFusion processes each
occurrence of each character as a delimiter.
Statement Output Comment
ListLen('a,b, c,,,d')
4 Third element is " c"
ListLen('a,b, c,,,d',',')
4 Fourth element is "d'"
ListLen('elem_1___elem_2___elem_3')
1
ListLen('elem*1***elem*2***elem*3')
1
ListLen('elem_1___elem_2___elem_3','_')
6