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 the Developing ColdFusion Applications

Parameters

Parameter

Description

list

A list or a variable that contains one.

delimiters

A string or a variable that contains one. Characters 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.

Usage

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

Here are some examples of ListLen processing:

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

 

Example

<h3>ListLen Example</h3> 
<!--- Find a list of users who wrote messages ---> 
<cfquery name = "GetMessageUser" datasource = "cfdocexamples"> 
    SELECT Username, Subject, Posted 
    FROMMessages 
</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>