So what really happens when we use 'new' in PHP

So what really happens when someone say 'new' in PHP

I believe in C/Java, when new is called, memory is allocated for each instance variables that are needed for an object? (correct me i开发者_运维百科f i am wrong)

Is this the same with PHP?

When you use $var = new Class

• a new object is created (memory allocated and initialized);
• its constructor, if any, is called;
• the object is put into a list of objects and given a unique id;
• a new zval container¹ is created, this container stores, inter alia, the id of the object;
• the variable $var is associated with this created zval container.

¹ Definition of what's a zval container.

The easiest way would be to check it for yourself using memory_get_usage()

echo memory_get_usage();
$obj1 = new obj1;
$obj2 = new obj2;
$obj3 = new obj3;
echo memory_get_usage();

Same is the case with PHP.

When you say new in PHP, PHP assumes you'd like to call a new Class: PHP Classes Basics.