Convert php string to array

In PHP programming, converting characters into arrays is a common operation. The most common application scenario is to split or split a string, convert it into an array and then traverse or analyze it. In PHP, there are many ways to convert a string into an array, including using built-in functions and custom functions. This article will introduce you to the methods and examples of converting PHP strings into arrays to help you better understand the operation.

1. Using the explode function

In PHP, the explode function is used to split a string into an array. explode The syntax of the function is as follows:

array explode( string $delimiter , string $string [, int $limit ] )

Among them:

• delimiter: splitting character, indicating what character or string to split.
• string: String to be split.
• limit: Indicates the maximum number of elements to be returned (all are returned by default). After the number of divided elements exceeds the limit, subsequent elements will not be returned.

The following is a simple example:

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

Output result:

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

In this example, we use comma as the dividing character to separate the stringapple,banana,orange Split into an array of three elements.

2. Using the str_split function

str_split function is used to split a string into substrings of a specified length, and Save these substrings in an array. str_split The syntax of the function is as follows:

array str_split ( string $string [, int $split_length = 1 ] )

Among them:

• string: the string to be split.
• split_length: Specify the length of each substring. If not specified, the length of each substring defaults to 1.

The following is an example:

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

Output result:

Array ( [0] => H [1] => e [2] => l [3] => l [4] => o [5] =>   [6] => W [7] => o [8] => r [9] => l [10] => d )

In this example, we split the string Hello World into An array of 11 elements. Each element is a character in the string.

3. Using custom functions

In addition to using built-in functions, we can also write custom functions to convert strings into arrays. The following is a basic custom function example:

function str2arr($str, $splitter = ",") {
    $arr = array();
    $pos = strpos($str, $splitter);
    while ($pos !== false) {
        $word = substr($str, 0, $pos);
        if ($word !== '') {
            $arr[] = $word;
        }
        $str = substr($str, $pos + 1);
        $pos = strpos($str, $splitter);
    }
    $arr[] = $str;
    return $arr;
}

In this function, we locate the separator position through the strpos() function, and then use substr() The function gets the string before the delimiter and finally stores the string into the array. The method of calling this function is as follows:

$str = "apple,banana,orange";
$arr = str2arr($str);
print_r($arr);

Output result:

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

In this example, we split the string apple,banana,orange into three An array of elements, using commas as separators.

Summary

This article introduces various methods of converting strings to arrays in PHP, including using the built-in functions explode() and str_split() , and custom functions. Through these methods, we can easily convert strings into arrays, providing convenient tools for analyzing and processing strings. Hope this article is helpful to you.

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