Scope in PHP
This article mainly introduces the scope of PHP, which has certain reference value. Now I share it with you. Friends in need can refer to the areas where variables can be accessed.
Scope in js:
Global scope: can be used anywhere (outside and inside the function)
Local scope: can only be used inside the function
PHP also has Two scopes: global scope and local scope
Global scope: can only be used outside the function
Local scope: can only be used inside the function
Global scope refers to For variables defined outside the function, the local scope refers to the variables defined inside the function
The outside cannot be accessed from the inside
The inside cannot be accessed from the outside
It can be accessed inside the function Use $GLOBALS['global scope variables'] in the local scope to access the global scope
Note: $GLOBALS refers to the variable that refers to the global scope itself
PHP also A keyword is provided: global
global is to copy the address of the variable in the global scope, then create a new variable name with the same name in the local scope, and assign the external address to the local variable.
Syntax: global variable name;
Variable name = value;
The area where the variable can be accessed.
Scope in js:
Global scope: can be used anywhere (outside and inside the function)
Local scope: can only be used inside the function
PHP also has Two scopes: global scope and local scope
Global scope: can only be used outside the function
Local scope: can only be used inside the function
Global scope refers to For variables defined outside the function, the local scope refers to the variables defined inside the function
The outside cannot be accessed from the inside
The inside cannot be accessed from the outside
It can be accessed inside the function Use $GLOBALS['global scope variables'] in the local scope to access the global scope
Note: $GLOBALS refers to the variable that refers to the global scope itself
PHP also A keyword is provided: global
global is to copy the address of the variable in the global scope, then create a new variable name with the same name in the local scope, and assign the external address to the local variable.
Syntax: global variable name;
Variable name = value;
The above is the entire content of this article. I hope it will be helpful to everyone's learning. For more related content, please pay attention to the PHP Chinese website!
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