How to convert string to array in PHP

PHP, as a server-side programming language, is widely used in the field of Web development. In web development, it is often necessary to convert strings into arrays for operations. This article will introduce how PHP converts a string into an array and explore the relevant knowledge points involved.

1. Methods of converting strings to arrays

In PHP, there are many ways to convert strings to arrays. These methods are introduced below.

1. Use the str_split() function

The str_split() function can split a string into individual characters and return an array composed of these characters. The following is an example:

$str = "Hello";
$arr = str_split($str);
print_r($arr);

The output result is as follows:

Array
(
    [0] => H
    [1] => e
    [2] => l
    [3] => l
    [4] => o
)

2. Use the explode() function

The explode() function can be used by the specified delimiter Split string into array. The following is an example:

$str = "apple,orange,banana";
$arr = explode(",", $str);
print_r($arr);

The output result is as follows:

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

3. Use the preg_split() function

The preg_split() function can divide the Split string into array. The following is an example:

$str = "apple1orange2banana";
$arr = preg_split("/\d+/", $str);
print_r($arr);

The output is as follows:

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

4. Use the str_word_count() function

str_word_count() function to split the string into words and returns an array containing the words. The following is an example:

$str = "Hello world!";
$arr = str_word_count($str, 1);
print_r($arr);

The output result is as follows:

Array
(
    [0] => Hello
    [1] => world
)

2. Split the string into arrays according to specified rules

In addition to the above methods, you can also use String specific rules for splitting a string into an array. Here are some examples:

1. Split the string into an array by the specified length

$str = "123456789";
$arr = str_split($str, 2);
print_r($arr);

The output results are as follows:

Array
(
    [0] => 12
    [1] => 34
    [2] => 56
    [3] => 78
    [4] => 9
)

2. Split the characters The string is split into an array according to the specified number of character repetitions

$str = "hello";
$arr = str_split(str_repeat($str, 3), strlen($str));
print_r($arr);

The output results are as follows:

Array
(
    [0] => h
    [1] => e
    [2] => l
    [3] => l
    [4] => o
    [5] => h
    [6] => e
    [7] => l
    [8] => l
    [9] => o
    [10] => h
    [11] => e
    [12] => l
    [13] => l
    [14] => o
)

3. Summary

This article introduces how to convert a string into Several methods for arrays, including using functions such as str_split(), explode(), preg_split(), and str_word_count(), as well as methods of splitting strings into arrays based on string-specific rules. In actual development, choosing the appropriate method to operate according to actual needs can improve development efficiency.

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