Adobe 38043740 - ColdFusion Standard - Mac Development Manual page 93

DEVELOPING COLDFUSION 9 APPLICATIONS
The CFML Programming Language
Adding an array element with a function
You can use the following array functions to add data to an array:
Function Description
ArrayAppend Creates an array element at the end of the array.
ArrayPrepend Creates an array element at the beginning of the array.
ArrayInsertAt Inserts an array element at the specified index position.
Because ColdFusion arrays are dynamic, if you add or delete an element from the array, any higher-numbered index
values all change. For example, the following code creates a two element array and displays the array contents. It then
uses to insert a new element at the beginning of the array and displays the result. The data that was
ArrayPrepend
originally in indexes 1 and 2 is now in indexes 2 and 3.
<!--- Create an array with three elements. --->
<cfset myarray=ArrayNew(1)>
<cfset myarray[1]="Original First Element">
<cfset myarray[2]="Original Second Element">
<!--- Use cfdump to display the array structure --->
<cfdump var=#myarray#>
<br>
<!--- Add a new element at the beginning of the array. --->
<cfscript>
ArrayPrepend(myarray, "New First Element");
</cfscript>
<!--- Use cfdump to display the new array structure. --->
<cfdump var=#myarray#>
For more information about these array functions, see the CFML Reference.
Deleting elements from an array
Use the function to delete data from the array at a particular index, instead of setting the data value
ArrayDeleteAt
to zero or an empty string. If you remove data from an array, the array resizes dynamically, as the following example
shows:
<!--- Create an array with three elements --->
<cfset firstname=ArrayNew(1)>
<cfset firstname[1]="Robert">
<cfset firstname[2]="Wanda">
<cfset firstname[3]="Jane">
<!--- Delete the second element from the array --->
<cfset temp=ArrayDeleteAt(firstname, 2)>
<!--- Display the array length (2) and its two entries,
which are now "Robert" and "Jane" --->
<cfoutput>
The array now has #ArrayLen(firstname)# indexes<br>
The first entry is #firstname[1]#<br>
The second entry is #firstname[2]#<br>
</cfoutput>
The function removed the original second element and resized the array so that it has two entries,
ArrayDeleteAt
with the second element now being the original third element.
Last updated 1/20/2012
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