How to pass array in php native method

In PHP, array is a very common and useful data type. PHP provides many native methods that allow us to easily manipulate arrays. So, how do we pass arrays in PHP?

In PHP, we can pass arrays to functions or methods in two ways: passing by value and passing by reference.

Passing by value refers to passing a copy of the array to a function or method. When modifying the passed array in a function or method, it has no effect on the original array. The advantage of this method is that it does not change the contents of the original array, but if the array is too large, using value passing will cause unnecessary memory overhead.

Passing by reference refers to passing the array itself to a function or method. In this way, when the array is modified in a function or method, the original array will be modified. Since the array itself is passed, there will be no additional memory overhead. However, it should be noted that if the original array is accidentally modified, it may have unexpected effects on the program.

Methods of passing arrays by value

In PHP, you can pass an array as a parameter to a function or method. The following code shows how to pass an array as a parameter:

<?php

function printArray($array) {
    foreach ($array as $value) {
        echo $value . " ";
    }
}

$array = array('apple', 'banana', 'orange');
printArray($array);

?>

In the above example, we have defined a function named printArray which has a parameter $array , this parameter is an array. We pass the array $array as a parameter to the printArray function, and in the function we loop through each element in the array and output their values.

How to pass an array by reference

In PHP, passing an array by reference is very similar to passing an array by value. The only difference is that when passing an array, in the parameters Add a & symbol in front of it. The following code shows how to pass an array using pass-by-reference:

<?php

function changeArray(&$array) {
    $array[0] = 'grape';
}

$array = array('apple', 'banana', 'orange');
changeArray($array);
print_r($array);

?>

In the above example, we have defined a function named changeArray that accepts one parameter $ array, this parameter is an array, and change the first element of the array to 'grape' in the function. In the main program, we define an array $array and then pass it as a parameter to the changeArray function. Note that when passing the array, we added a & symbol before the parameter. Finally, we use the print_r function to output the variable $array to confirm whether the array has been modified.

Summary:

In PHP, we can pass arrays using value pass and reference pass. If we just want to read the values ​​in the array, use passing by value. If we want to modify the values ​​in the array, use pass by reference. It should be noted that when passing by reference, you must be very careful to ensure that the contents of the original array are not changed.

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