Parameter
Last updated on
May 16, 2021
|
Also applies to ColdFusion
Description
Concatenates a list or element to a list.
Returns
A string.
Category
Function syntax
ListAppend(list, value [, delimiter, includeEmptyFields ])
See also
ListPrepend, ListInsertAt, ListGetAt, ListLast, ListSetAt; Lists in the Developing ColdFusion Applications.
History
ColdFusion (2018 release) Update 5:
- Introduced named parameters.
- New parameter added- includeEmptyFields.
Parameters
|
|
Description |
|---|---|
|
list |
A list or a variable that contains a list. |
|
value |
An element or a list of elements. |
|
delimiters |
(Optional) 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 uses only the first character. |
|
includeEmptyFields |
Boolean to determine to include empty fields from the list that is appended to the list. |
Usage
ColdFusion inserts a delimiter character before value. The following table shows examples of ListAppend processing:
Statement |
Output |
Comment |
|---|---|---|
ListAppend('elem1,elem2', '' ) |
elem1,elem2, |
Appended element is empty; delimiter is last character in list; list length is 2. |
ListAppend('', 'elem1,elem2' ) |
elem1,elem2 |
List length is 2. |
ListAppend("one__two", "three", "__") |
"one two_three" |
Inserted the first character of delimiters before "three." |
Example 1
<cfscript>
myList="John,Paul,George,Ringo";
myListAppended=ListAppend(myList,"George Martin",","); // Delimiter is comma
WriteOutput(myListAppended);
</cfscript>
Output
John,Paul,George,Ringo,George Martin
<cfscript>
// define the list
myList="John,Paul,George,Ringo";
myListAppended=ListAppend(myList,"George Martin");
WriteOutput(myListAppended);
</cfscript>
Output
John,Paul,George,Ringo,George Martin
Example 3
<cfscript>
myList="John";
myListAppended=ListAppend(myList,"George Martin","|");
WriteOutput(myListAppended);
</cfscript>
Output
John|George Martin
Example 3
When includeEmptyFields="true",
<cfscript> mylist="John,Paul,George" writeOutput(ListAppend(list=mylist,value="Ringo,,",delimiter=",",includeEmptyFields="true")) </cfscript>
Output
John,Paul,George,Ringo,,
<cfscript> mylist="John,Paul" writeOutput(ListAppend(list=mylist,value="Ringo,George,",delimiter=",",includeEmptyFields="true")) </cfscript>
Output
John,Paul,Ringo,George,
Example 4
When includeEmptyFields="false",
<cfscript> mylist="John,Paul,George" writeOutput(ListAppend(list=mylist,value="Ringo,,",delimiter=",",includeEmptyFields="false")) </cfscript>
Output
John,Paul,George,Ringo
<cfscript> mylist="John,Paul" writeOutput(ListAppend(list=mylist,value="Ringo,George,",delimiter=",",includeEmptyFields="false")) </cfscript>
Output
John,Paul,George,Ringo
Member function
<cfscript>
mylist="John,Paul,,"
writeOutput(mylist.Append("Ringo,George,",",","false"))
</cfscript>
Output
John,Paul,Ringo,George