Php pass object by reference

One of the key-points of PHP OOP that is often mentioned is that "objects are passed by references by default". This is not completely true. This section rectifies that general thought using some examples.

A PHP reference is an alias, which allows two different variables to write to the same value. In PHP, an object variable doesn't contain the object itself as value. It only contains an object identifier which allows object accessors to find the actual object. When an object is sent by argument, returned or assigned to another variable, the different variables are not aliases: they hold a copy of the identifier, which points to the same object.

Example #1 References and Objects

The above example will output:

miklcct at gmail dot com ¶

12 years ago

Notes on reference: A reference is not a pointer. However, an object handle IS a pointer. Example:

lazybones_senior ¶

13 years ago

WHOA... KEEP IT SIMPLE!

In regards to secure_admin's note: You've used OOP to simplify PHP's ability to create and use object references. Now use PHP's static keyword to simplify your OOP.

DataModelControl [name=dmc1, data=256] DataModelControl [name=dmc2, data=256] DataModelControl [name=dmc3, data=256]

DataModelControl [name=dmc1, data=1024] DataModelControl [name=dmc2, data=1024] DataModelControl [name=dmc3, data=1024]

... even better! Now, PHP creates one copy of $data, that is shared amongst all DataModelControl objects.

Is PHP pass by reference or pass by value?

Introduction. In PHP, arguments to a function can be passed by value or passed by reference. By default, values of actual arguments are passed by value to formal arguments which become local variables inside the function. Hence, modification to these variables doesn't change value of actual argument variable.

Are objects always passed by reference?

Objects are always passed by reference . That is, when passing an object to a function, the function will act on the same object. If the object changes inside the function, the change will be reflected outside the function. This is an extension of the behavior of assigning an object to a new variable.

Are PHP arrays passed by reference?

With regards to your first question, the array is passed by reference UNLESS it is modified within the method / function you're calling. If you attempt to modify the array within the method / function, a copy of it is made first, and then only the copy is modified.

How do you reference in PHP?

In PHP, variable name and variable content are different, so the same content can have different names. A reference variable is created by prefixing & sign to original variable. Hence b=&a will mean that bisareferewncevariableofa.

Is PHP pass by reference or pass by value?

Are objects always passed by reference?

Are PHP arrays passed by reference?

How do you reference in PHP?

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