How to add array elements in php

In PHP, we can add elements to an array in many ways. This article will introduce three commonly used methods: using indexes, using key-value pairs, and using the array_push() function.

1. Using Indexes

The most basic way to add elements to an array is to use integer indexing. Suppose we have the following array:

$fruits = array("apple", "banana", "orange");

We can add new elements by index:

$fruits[3] = "grapes";

This line of code will add a new element "grapes" to the array and change its index Set to 3. In this way, we can use the index to access this element:

echo $fruits[3]; //输出 "grapes"

2. Using key-value pairs

In addition to using integer indexes, we can also use key-value pairs (key -value pairs) to add elements to the array. We can achieve this using associative arrays. Suppose we need to create an array containing student information:

$student = array(
    "name" => "Tom",
    "age" => 18,
    "grade" => "A"
);

This array contains the student's name, age, and grades. We can add new elements to it like this:

$student["email"] = "tom@example.com";

This will add a new key-value pair in the array and assign it the value "tom@example.com". We can use this key to access and modify this element:

echo $student["email"]; //输出 "tom@example.com"

3. Using the array_push() function

PHP also provides a convenient function array_push(), which can be used to add one or more elements to the end of the array. For example:

$colors = array("red", "green", "blue");
array_push($colors, "yellow", "purple");

In this example, we add two new elements, "yellow" and "purple" to the $colors array. We can use the print_r() function to view the contents of this array:

print_r($colors);

The output results are as follows:

Array
(
    [0] => red
    [1] => green
    [2] => blue
    [3] => yellow
    [4] => purple
)

Conclusion

Through this article, we learned to use indexes and keys Value pairs and add elements to a PHP array using the array_push() function. These methods are simple and practical, and can help developers quickly operate arrays. In actual development, we need to choose the most suitable method according to the specific situation.

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