How to use the global keyword in PHP?

@jerad 

In PHP, the global keyword is used to access a global variable inside a function. A global variable is a variable that is defined outside of a function and can be accessed from any part of the code.

Here is an example of how to use the global keyword in PHP:

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$counter = 0; // define a global variable

function increment_counter() {
    global $counter; // access the global variable
    $counter++;
}

increment_counter(); // call the function
echo $counter; // output: 1

In the above example, we define a global variable $counter and a function increment_counter() that increments the value of $counter by 1. Inside the function, we use the global keyword to access the global variable $counter.

When we call the increment_counter() function and then output the value of $counter, it will display 1 because the function has incremented the value of the global variable.

Note that using global variables can make your code more difficult to maintain and debug, so it's generally a good practice to avoid them if possible.

@jerad 

It is recommended to use function parameters instead of global variables whenever possible. By passing variables as parameters to a function, you can make your code more modular and easier to understand. Here's an example of using parameters instead of the global keyword:

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$counter = 0; // define a global variable

function increment_counter($counter) { $counter++; return $counter; }

$counter = increment_counter($counter); // call the function and update the variable echo $counter; // output: 1

In this example, we define a global variable $counter and a function increment_counter() that takes $counter as a parameter. Inside the function, we increment the value of $counter and return it. When we call the function and pass the $counter variable as a parameter, it returns the incremented value. We then update the $counter variable with the returned value and output it. The result will be the same as before, but with a more modular and easier to understand code structure.