Adobe ColdFusion 8

ArrayIsDefined

Description

Determines whether an array element is defined.

Returns

True, if the array element is defined (exists); false, otherwise.

Category

Array functions

Function syntax

ArrayIsDefiend(array, elementIndex)

See also

ArrayIsEmpty

History

ColdFusion 8: Added this function.

Parameters

Parameter

Description

array

Name of a one dimensional array, or the array name and indexes into higher-order dimensions of a multidimensional array.

elementIndex

Index of the element in a one dimensional array, or the index of the element in the final dimension of a multidimensional array.

Usage

To test the existence of an element in a multidimensional array, specify all but the last dimension of the array in the first parameter. For example, the following line tests the existence of element MyArray[2][4][1]:

ArrayIsDefined(MyArray[2][4], 1)

Example

<h3>ArrayIsDefined Example</h3>
<!--- Create a sparse new array. --->
<cfset MyArray = ArrayNew(1)>
<!--- Populate an element or two. --->
<cfset MyArray[1] = "Test">
<cfset MyArray[3] = "Other Test">

<cfoutput>
    <!--- Display the contents of the array. --->
    <p>Your array contents are:
    <cfdump var="#MyArray#"></p>
    
    <!--- Check if an existing element is defined. --->
    <p>Does element 3 exist?:&nbsp;
    #ArrayIsDefined(MyArray, 3)#</p>
    
    <!--- Check if a non-existent element is defined. --->
    <p>Does element 2 exist?&nbsp;
    #ArrayIsDefined(MyArray, 2)#
</cfoutput>