Basic array techniques
107
The best way to understand an asymmetrical array is by looking at it. The following example
creates an asymmetric, multidimensional array and the
cfdump
tag displays the resulting array
structure. Several array elements do not yet contain data.
<cfset myarray=ArrayNew(1)>
<cfset myotherarray=ArrayNew(2)>
<cfset biggerarray=ArrayNew(3)>
<cfset biggerarray[1][1][1]=myarray>
<cfset biggerarray[1][1][1][10]=3>
<cfset biggerarray[2][1][1]=myotherarray>
<cfset biggerarray[2][1][1][4][2]="five deep">
<cfset biggestarray=ArrayNew(3)>
<cfset biggestarray[3][1][1]=biggerarray>
<cfset biggestarray[3][1][1][2][3][1]="This is complex">
<cfset myarray[3]="Can you see me">
<cfdump var=#biggestarray#>
<br>
<cfdump var=#myarray#>
Note:
The
cfdump
tag displays the entire contents of an array. It is an excellent tool for debugging
arrays and array-handling code.
Reviewing the code
The following table describes the code:
Code
Description
<cfset myarray=ArrayNew(1)>
<cfset myotherarray=ArrayNew(2)>
<cfset biggerarray=ArrayNew(3)>
Create three empty arrays, a 1D array, a 2D array, and a 3D
array.
<cfset
biggerarray[1][1][1]=myarray>
<cfset biggerarray[1][1][1][10]=3>
Make element [1][1][1] of the 3D biggerarray array be a copy
of the 1D array. Assign 3 to the [1][1][1][10] element of the
resulting array.
The biggerarray array is now asymmetric. For example, it
does not have a [1][1][2][1] element.
<cfset biggerarray[2][1][1]=
myotherarray>
<cfset biggerarray[2][1][1][4][2]=
"five deep">
Make element [2][1][1] of the 3D array be the 2D array, and
assign the [2][1][1][4][2] element the value "five deep".
The biggerarray array is now even more asymmetric.
<cfset biggestarray=ArrayNew(3)>
<cfset biggestarray[3][1][1]
=biggerarray>
<cfset
biggestarray[3][1][1][2][3][1]
="This is complex">
Create a second 3D array. Make the [3][1][1] element of this
array be a copy of the bigerarray array, and assign element
[3][1][1][2][3][1].
The resulting array is very complex and asymmetric.
<cfset myarray[3]="Can you see
me">
Assign a value to element [3] of myarray.
<cfdump var=#biggestarray#><br>
<cfdump var=#myarray#>
Use
cfdump
to view the structure of biggestarray and
myarray.
Notice that the "Can you see me" entry appears in myarray,
but not in biggestarray, because biggestarray has a copy of
the original myarray values and is not affected by the change
to myarray.
Содержание COLDFUSION MX 61-DEVELOPING COLDFUSION MX
Страница 1: ...Developing ColdFusion MX Applications...
Страница 22: ...22 Contents...
Страница 38: ......
Страница 52: ...52 Chapter 2 Elements of CFML...
Страница 162: ......
Страница 218: ...218 Chapter 10 Writing and Calling User Defined Functions...
Страница 250: ...250 Chapter 11 Building and Using ColdFusion Components...
Страница 264: ...264 Chapter 12 Building Custom CFXAPI Tags...
Страница 266: ......
Страница 314: ...314 Chapter 14 Handling Errors...
Страница 344: ...344 Chapter 15 Using Persistent Data and Locking...
Страница 349: ...About user security 349...
Страница 357: ...Security scenarios 357...
Страница 370: ...370 Chapter 16 Securing Applications...
Страница 388: ...388 Chapter 17 Developing Globalized Applications...
Страница 408: ...408 Chapter 18 Debugging and Troubleshooting Applications...
Страница 410: ......
Страница 426: ...426 Chapter 19 Introduction to Databases and SQL...
Страница 476: ...476 Chapter 22 Using Query of Queries...
Страница 534: ...534 Chapter 24 Building a Search Interface...
Страница 556: ...556 Chapter 25 Using Verity Search Expressions...
Страница 558: ......
Страница 582: ...582 Chapter 26 Retrieving and Formatting Data...
Страница 668: ......
Страница 734: ...734 Chapter 32 Using Web Services...
Страница 760: ...760 Chapter 33 Integrating J2EE and Java Elements in CFML Applications...
Страница 786: ...786 Chapter 34 Integrating COM and CORBA Objects in CFML Applications...
Страница 788: ......
Страница 806: ...806 Chapter 35 Sending and Receiving E Mail...