How to modify the value of an array in PHP (three methods)

PHP, as a scripting language, is very commonly used in web development, and modifying array values ​​is also one of the common operations. This article will introduce how to modify array values ​​through PHP.

1. Modify array elements by index

In PHP, the index of an array element can be a number or a string. We can modify the value of one of the elements through the index of the array.

Sample code:

$fruit = array('apple', 'banana', 'cherry');  //定义一个数组
$fruit[1] = 'orange';  //通过索引修改数组元素
print_r($fruit);  //输出修改后的数组

Running result:

Array
(
    [0] => apple
    [1] => orange
    [2] => cherry
)

In the above sample code, we modified it in the form of $fruit[1] The element at index 1 in the array is changed from 'banana' to 'orange'.

2. Modify array elements through key names

In addition to modifying array elements through indexes, we can also modify the value of one of the elements through the key name of the array. This method will More convenient and in some cases more applicable.

Sample code:

$info = array('name' => 'Tom', 'age' => 20, 'gender' => 'male');  //定义一个关联数组
$info['age'] = 21;  //通过键名修改数组元素
print_r($info);  //输出修改后的数组

Running result:

Array
(
    [name] => Tom
    [age] => 21
    [gender] => male
)

In the above sample code, we use the form $info['age'] The element with the key name 'age' in the array was modified from the original 20 to 21.

3. Modify array elements through loops

In addition to the above two methods, we can also modify the element values ​​in the array through loops. This method is suitable for situations where array elements need to be modified in batches.

Sample code:

$score = array(89, 92, 78, 85, 94);  //定义一个数组
for($i=0; $i<count($score); $i++){  //循环修改数组元素
    $score[$i] += 5;
}
print_r($score);  //输出修改后的数组

Running result:

Array
(
    [0] => 94
    [1] => 97
    [2] => 83
    [3] => 90
    [4] => 99
)

In the above sample code, we traverse the array through a for loop and increase the value of each element by 5 .

Summary

Through the above three methods, we can modify the element values ​​in the PHP array. Among them, the method of modifying array elements by key name is more flexible and can be changed at will according to your own needs. When modifying the element values ​​in an array in batches through a loop, you need to pay attention to avoid the array going out of bounds. I hope this article can be helpful to PHP beginners.

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