User Guide

Populating Arrays with Data 121

Populating Arrays with Data

Array elements can store any values, including queries, structures, and other arrays.

You can use a number of functions to populate an array with data, including

ArraySet, ArrayAppend, ArrayInsertAt, and ArrayPrepend. These functions are

useful for adding data to an existing array.

In particular you should master the following basic techniques:

• Populating an array with

ArraySet

• Populating an array with cfloop

• Populating an array from a query

Populating an array with ArraySet

You can use the ArraySet function to populate a 1D, or one dimension of a

multidimensional array, with some initial value such as an empty string or 0 (zero).

This can be useful if you need to create an array of a certain size, but do not need to

add data to it right away. One reason to do this is so that you can refer to all the array

indexes. If you refer to an array index that does not contain some value, such as an

empty string, you get an error.

The

ArraySet function has the following form:

ArraySet (arrayname, startrow, endrow, value)

This example initializes the array myarray, indexes 1 to 100, with an empty string.

ArraySet (myarray, 1, 100, "")

Populating an array with cfloop

A common and very efficient method for populating an array is by creating a looping

structure that adds data to an array based on some condition using

cfloop.

The following example uses a

cfloop tag and the MonthAsString function to

populate a simple 1D array with the names of the months. A second

cfloop outputs

data in the array to the browser.

</cfloop>

#months[loopcount]#<br>

</cfoutput>

</cfloop>