ColdFusion structures consist of key-value pairs, where the keys are text strings and the values can be any ColdFusion data type, including other structures. Structures let you build a collection of related variables that are grouped under a single name. To create a structure, use the ColdFusion StructNew function. For example, the following line creates a new, empty, structure called depts:

<cfset depts=StructNew()>

You can also create a structure by assigning a value in the structure. For example, the following line creates a new structure called MyStruct with a key named MyValue, equal to 2:

<cfset MyStruct.MyValue=2>

After you create a structure, you can use functions or direct references to manipulate its contents, including adding key-value pairs.

You can use either of the following methods to reference elements stored in a structure:

• StructureName.KeyName
• StructureName["KeyName"]

The following examples show these methods:

depts.John="Sales"
depts["John"]="Sales"

When you assign an existing structure to a new variable, ColdFusion does not create a new structure. Instead, the new variable accesses the same data (location) in memory as the original structure variable. In other words, both variables are references to the same object.

For example, the following line creates a new variable, myStructure2, that is a reference to the same structure as the myStructure variable:

<cfset myStructure2=myStructure>

When you change the contents of myStructure2, you also change the contents of myStructure. To copy the contents of a structure, use the ColdFusion Duplicate function, which copies the contents of structures and other complex data types.

Structure key names can be the names of complex data objects, including structures or arrays. This lets you create arbitrarily complex structures.

For more information on using structures, see Using Arrays and Structures.