Referencing complex structures

When a structure contains another structure, you reference the data in the nested structure by extending either object.property or associative array notation. You can even use a mixture of both notations.

For example, if structure1 has a key key1 whose value is a structure that has keys struct2key1, struct2key2, and so on, you can use any of the following references to access the data in the first key of the embedded structure:

Structure1.key1.Struct2key1 
Structure1["key1"].Struct2key1 
Structure1.key1["Struct2key1"] 
Structure1["key1"]["Struct2key1"]

The following example shows various ways you can reference the contents of a complex structure:

<cfset myArray=ArrayNew(1)> 
<cfset myArray[1]="2"> 
<cfset myArray[2]="3"> 
<cfset myStruct2=StructNew()> 
<cfset myStruct2.struct2key1="4"> 
<cfset myStruct2.struct2key2="5"> 
<cfset myStruct=StructNew()> 
<cfset myStruct.key1="1"> 
<cfset myStruct.key2=myArray> 
<cfset myStruct.key3=myStruct2> 
<cfdump var=#myStruct#><br> 
 
<cfset key1Var="key1"> 
<cfset key2Var="key2"> 
<cfset key3Var="key3"> 
<cfset var2="2"> 
 
<cfoutput> 
Value of the first key<br> 
#mystruct.key1#<br> 
#mystruct["key1"]#<br> 
#mystruct[key1Var]#<br> 
<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> 
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> 
</cfoutput>

Reviewing the code

The following table describes the code:

Code

Description

 
<cfset myArray=ArrayNew(1)> 
<cfset myArray[1]="2"> 
<cfset myArray[2]="3"> 
<cfset myStruct2=StructNew()> 
<cfset myStruct2.struct2key1="4"> 
<cfset myStruct2.struct2key2="5"> 
<cfset myStruct=StructNew()> 
<cfset myStruct.key1="1"> 
<cfset myStruct.key2=myArray> 
<cfset myStruct.key3=myStruct2>

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

 
<cfdump var=#myStruct#><br>

Display the complete structure.

 
<cfset key1Var="key1"> 
<cfset key2Var="key2"> 
<cfset 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