What is Local Variable Scope in PHP?

What is Local Variable Scope in PHP?

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  • PHP
  • 2 mins read

What is Variable Scope in PHP?

The variable scope defines the visibility of variables in PHP programs. In PHP there are three variable scopes. These are given below:

(i) Local Scope
(ii) Global Scope
(iii) Static Scope

What is the Local Variable Scope in PHP?

In PHP, when a variable is declared within a function, that variable will contain local scope. Local variable will be accessed and visible only within that function where that will be declared.

Now we will write a program on the local scope of a variable:

In this program, we will define a function f1. Within the function body, there is a local variable $a with an initialized string "welcome" here, and we will try to access that variable outside the function.

<html>
    <body>
        <?php
function f1()
{
    $a="welcome"; //$a variable has a local scope
    echo $a;
}
f1(); //function calling
echo $a; //error beacuse local variable is accessing outside the function
        ?>
    </body>
</html>

Output

welcome
E_NOTICE : type 8 -- Undefined variable: a -- at line 10

In the above program, the variable $a has a local scope. After executing the program, there will be an error, because variable $a is accessing outside the function.

Here is a PHP program using a local variable within a function with an initialized value.

In this program, we will use a user-defined function f1, and we will declare a local variable $a with initialized to 5 inside the function then we call the function for three times:

<html>
    <body>
        <?php
function f1()
{
    $a=5; //local scope
    $a=$a+1; //increasing value
    echo $a."<br>";
}
f1(); //function calling
f1(); //function calling
f1(); //function calling
        ?>
    </body>
</html>

Output

6
6
6

Here function is calling for three times. Local variable will be initialized for every time for each calling of a function(where the local variable is declared). So the outputs are 6,6 and 6.