How to solve the problem of handling Chinese strings when using array_count_values() function?

How to solve the problem of handling Chinese strings when using array_count_values() function?

In PHP, the array_count_values() function is used to calculate the frequency of occurrence of all values ​​in an array. However, when you use this function to handle Chinese strings, you may encounter some problems, especially when it comes to character encoding issues. This article will explore how to solve this problem and provide solutions.

1. Problem analysis

The main function of the array_count_values() function is to return an associative array, where the keys are different values ​​that appear in the array, and the values ​​are the number of times these values ​​appear. This function works fine when dealing with English characters, but for Chinese strings it may have unexpected behavior. The reason is usually a character encoding problem.

PHP uses ISO-8859-1 encoding to process strings by default, but Chinese characters are usually encoded by UTF-8. Due to inconsistent encoding, array_count_values() may not count the frequency of Chinese characters correctly, especially when strings contain multibyte characters.

2. Case Study

Suppose you have an array containing Chinese strings:

 <?php
$array = ['apple', 'banana', 'apple', 'tangerine', 'banana', 'apple'];
print_r(array_count_values($array));
?>

The expected output is:

 Array
(
    [apple] => 3
    [banana] => 2
    [tangerine] => 1
)

However, in some cases, you may encounter incorrect output or garbled code.

3. Solution

To solve this problem, you can use the following methods:

3.1 Character encoding conversion using mb_string extension

To ensure that Chinese strings can be processed correctly, you can first use the mb_convert_encoding() or mb_strlen() function to convert the encoding format of the string to avoid encoding problems.

Here is a solution:

 <?php
// Make sure to useUTF-8coding
$array = ['apple', 'banana', 'apple', 'tangerine', 'banana', 'apple'];

// Convert toUTF-8coding
$array = array_map(function($item) {
    return mb_convert_encoding($item, 'UTF-8', 'auto');
}, $array);

// use array_count_values function
print_r(array_count_values($array));
?>

This ensures that the Chinese strings are used in UTF-8 encoding when processing, avoiding the problem of inconsistent encoding.

3.2 Preprocessing strings, removing spaces and other non-Chinese characters

If you find that spaces or other non-Chinese characters affect the statistics, you can use the preg_replace() function to filter out these irrelevant characters.

 <?php
$array = ['apple', 'banana', 'apple', 'tangerine', 'banana', 'apple'];

// Remove non-Chinese characters
$array = array_map(function($item) {
    return preg_replace('/[^\x{4e00}-\x{9fa5}]/u', '', $item);
}, $array);

print_r(array_count_values($array));
?>

3.3 Functions supported by using multibyte characters

If you have already installed the mbstring extension in your environment, using multibyte string functions such as mb_strlen() may have better results. You can use these functions to ensure that the string processing conforms to the characteristics of multibyte characters.

 <?php
$array = ['apple', 'banana', 'apple', 'tangerine', 'banana', 'apple'];

// use mb_strlen() To determine the length of the string
$array = array_map(function($item) {
    return mb_convert_encoding($item, 'UTF-8', 'auto');
}, $array);

print_r(array_count_values($array));
?>

4. Summary

When using array_count_values() to process Chinese strings in PHP, a common problem is inconsistent character encoding. To avoid this problem, you can ensure that Chinese characters are properly processed through the following steps:

• Make sure all strings are encoded using UTF-8;

• Before processing strings, use the appropriate function for character encoding conversion;

• Filter out irrelevant characters to ensure that only Chinese characters participate in the statistics.

Through the above method, you can successfully solve the problem of handling Chinese strings in array_count_values() .