您必须修改代码才能提供关系.在OOP中,我们称之为

aggregation.

假设PHP 4,以及“一系列条形图”的想法

class foo {

var $bars = array();

function __construct() {

"Foo Exists!";

}

function magic_bullet($id) {

switch($id) {

case 1:

echo "There is no spoon! ";

case 2:

echo "Or is there... ";

break;

}

}

function addBar( &$bar )

{

$bar->setFoo( $this );

$this->bars[] = &$bar;

}

}

class bar {

var $foo;

function __construct() {

echo "Bar exists";

}

function target($id){

if ( isset( $this->foo ) )

{

echo $this->foo->magic_bullet( $id );

} else {

trigger_error( 'There is no foo!', E_USER_ERROR );

}

}

function setFoo( &$foo )

{

$this->foo = &$foo;

}

}

$test = new foo();

$bar1 = new bar();

$bar2 = new bar();

$test->addBar( $bar1 );

$test->addBar( $bar2 );

$bar1->target( 1 );

$bar1->target( 2 );