About structures

Object.property

You can reference a property, prop, of an object, obj, as obj.prop. This notation, also called dot notation, is useful for simple assignments, as in this example:depts.John="Sales"
Use this notation only when you know the property names (keys) in advance and they are strings, with no special characters, numbers, or spaces. You cannot use the dot notation when the property, or key, is dynamic.

Associative arrays

If you do not know the key name in advance, or it contains spaces, numbers, or special characters, you can use associative array notation. This notation uses structures as arrays with string indexes; for example:
depts["John"]="Sales"
depts[employeeName] = "Sales"
You can use a variable (such as employeeName) as an associative array index. Therefore, enclose any literal key names in quotation marks. For information on using associative array references containing variables, see Dynamically constructing structure references in Dynamic expressions and dynamic variables.

Structure

Use structure notation only when you create structures and set their initial values, not when you are accessing or updating structure data, and only on the right side of an assignment expression. This notation has the following format:
{keyName=value[,keyName=value]...}
where the square braces ([]) and ellipses (\...) indicate optional contents that can be repeated.The following example creates a structure that uses structure notation:
<cfset name={firstName = "John", lastName = "Smythe"}>

<cfscript>

myArray=ArrayNew(1);

myArray[1]="2";

myArray[2]="3";

myStruct2=StructNew();

myStruct2.struct2key1="4";

myStruct2.struct2key2="5";

myStruct=StructNew();

myStruct.key1="1";

myStruct.key2=myArray;

myStruct.key3=myStruct2;

</cfscript>

Create a structure with three entries: a string, an array, and an embedded structure.

writeDump( var=myStruct );

Display the complete structure.

key1Var="key1";

key2Var=""key2;

key3Var="key3";

Create variables containing the names of the myStruct keys and the number 2.

<cfoutput> 
Value of the first key<br> 
#mystruct.key1#<br> 
#mystruct["key1"]#<br> 
#mystruct[key1Var]#<br> 
<br>

Output the value of the key1 (string) entry using the following notation:

• object.property notation
• associative array notation with a constant
• associative array notation with a variable

<br> 
Value of the second entry in the key2 array<br> 
#myStruct.key2[2]#<br> 
#myStruct["key2"][2]#<br> 
#myStruct[key2Var][2]#<br> 
#myStruct[key2Var][var2]#<br> 
<br>

Output the value of the second entry in the key2 array using the following notation:

• object.property notation
• associative array notation with a constant
• associative array notation with a variable
• associative array notation with variables for both the array and the array index

Value of the struct2key2 entry in the key3 structure<br> 
#myStruct.key3.struct2key2#<br> 
#myStruct["key3"]["struct2key2"]#<br> 
#myStruct[key3Var]["struct2key2"]#<br> 
#myStruct.key3["struct2key2"]#<br> 
#myStruct["key3"].struct2key2#<br> 
<br>

Output the value of second entry in the key3 embedded structure using the following notation:

• object.property notation
• associative array notation with two constants
• associative array notation with a variable and a constant
• object.property notation followed by associative array notation
• associative array notation followed by object.property notation