note 46290 modified in language.oop5 by danbrown
| From: | danbrown@php.net | Date: | Mon, 15 Feb 2010 18:10:55 +0000 |
| Subject: | note 46290 modified in language.oop5 by danbrown | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-165977@lists.php.net to get a copy of this message | ||
PHP 5 is very very flexible in accessing member variables and member functions. These access methods
maybe look unusual and unnecessary at first glance; but they are very useful sometimes; specially
when you work with SimpleXML classes and objects. I have posted a similar comment in SimpleXML
function reference section, but this one is more comprehensive.
I use the following class as reference for all examples:
<?php
class Foo {
public $aMemberVar = 'aMemberVar Member Variable';
public $aFuncName = 'aMemberFunc';
function aMemberFunc() {
print 'Inside
aMemberFunc()';
}
}
$foo = new Foo;
?>
You can access member variables in an object using another variable as name:
<?php
$element = 'aMemberVar';
print $foo->$element; // prints "aMemberVar Member Variable"
?>
or use functions:
<?php
function getVarName()
{ return 'aMemberVar'; }
print $foo->{getVarName()}; // prints "aMemberVar Member Variable"
?>
Important Note: You must surround function name with { and } or PHP would think you are calling a
member function of object "foo".
you can use a constant or literal as well:
<?php
define(MY_CONSTANT, 'aMemberVar');
print $foo->{MY_CONSTANT}; // Prints "aMemberVar Member Variable"
print $foo->{'aMemberVar'}; // Prints "aMemberVar Member Variable"
?>
You can use members of other objects as well:
<?php
print $foo->{$otherObj->var};
print $foo->{$otherObj->func()};
?>
You can use mathods above to access member functions as well:
<?php
print $foo->{'aMemberFunc'}(); // Prints "Inside aMemberFunc()"
print $foo->{$foo->aFuncName}(); // Prints "Inside aMemberFunc()"
?>
--was--
PHP 5 is very very flexible in accessing member variables and member functions. These access methods
maybe look unusual and unnecessary at first glance; but they are very useful sometimes; specially
when you work with SimpleXML classes and objects. I have posted a similar comment in SimpleXML
function reference section, but this one is more comprehensive.
I use the following class as reference for all examples:
<?
class Foo {
public $aMemberVar = 'aMemberVar Member Variable';
public $aFuncName = 'aMemberFunc';
function aMemberFunc() {
print 'Inside aMemberFunc()';
}
}
$foo = new Foo;
?>
You can access member variables in an object using another variable as name:
<?
$element = 'aMemberVar';
print $foo->$element; // prints "aMemberVar Member Variable"
?>
or use functions:
<?
function getVarName()
{ return 'aMemberVar'; }
print $foo->{getVarName()}; // prints "aMemberVar Member Variable"
?>
Important Note: You must surround function name with { and } or PHP would think you are calling a
member function of object "foo".
you can use a constant or literal as well:
<?
define(MY_CONSTANT, 'aMemberVar');
print $foo->{MY_CONSTANT}; // Prints "aMemberVar Member Variable"
print $foo->{'aMemberVar'}; // Prints "aMemberVar Member Variable"
?>
You can use members of other objects as well:
<?
print $foo->{$otherObj->var};
print $foo->{$otherObj->func()};
?>
You can use mathods above to access member functions as well:
<?
print $foo->{'aMemberFunc'}(); // Prints "Inside aMemberFunc()"
print $foo->{$foo->aFuncName}(); // Prints "Inside aMemberFunc()"
?>
http://php.net/manual/en/language.oop5.php