Php simply intercepts a mix of Chinese and English strings. only two lines of code are required!

Php simply intercepts a mix of Chinese and English strings. only two lines of code are required!

When talking about Chinese and English mixed sorting and truncation, we first think of ascii, hexadecimal, regular matching, and cyclic counting. Today, I want to share with you how to easily process strings through the mb extension of php. First, we will introduce the functions used: Mb_strwidth ($ str, $ encoding) returns the string width. $ Str string to be calculated $ Encoding used by encoding, such as utf8 and gbk Mb_strimwidth ($ str, $ start, $ width, $ tail, $ encoding) truncates a string by its width. $ Str string to be truncated $ Start: where to start the truncation. the default value is 0. $ Width: the width to be truncated. $ Tail appends the string to the string behind the truncated string, which is commonly used... $ Encoding used by encoding The following is an example: /** * Utf8 encoding format * One Chinese character occupies 3 bytes * What we want is that one Chinese character occupies 2 bytes, * Because the two English letters occupy the same position as one Chinese character in width */ // Test string $ Str = 'aaaa, aaaa, aaa '; Echo strlen ($ str); // only use strlen to output 25 bytes // The encoding must be specified. Otherwise, the php internal code mb_internal_encoding () will be used to view the internal code. // Use mb_strwidth to output a string whose width is 20 and utf8 encoding Echo mb_strwidth ($ str, 'utf8 '); // Intercept only when the width is greater than 10 If (mb_strwidth ($ str, 'utf8')> 10 ){ // The screenshot starts from 0, and 10 appends are obtained. UTF-8 encoding is used. // Note that the append... will be calculated within the length. $ Str = mb_strimwidth ($ str, 0, 10, '...', 'utf8 '); } // Output aaaa at the end... 4 a counts 4 and 1. calculate 2 and 3. calculate 3. 4 + 2 + 3 = 9. // Isn't it easy? some people have said why 9 is not 10? // Because "ah" is followed by "ah", the number of Chinese characters is counted as 2. 9 + 2 = 11 has exceeded the setting, so the number of Chinese characters removed is 9. Echo $ str; I will introduce some other functions below: Mb_strlen ($ str, $ encoding) returns the length of the string. $ Str string to be calculated $ Encoding used by encoding Mb_substr ($ str, $ start, $ length, $ encoding) intercepts a string $ Str string to be truncated $ Start $ Length $ Encoding used by encoding In fact, these two functions are very similar to strlen () and substr (). The only difference is that encoding can be set. Bottom edge instance: /** * Utf8 encoding format * One Chinese character occupies 3 bytes */ $ Str = 'aa12 Ah '; Echo strlen ($ str); // The direct output length is 9. // The output length is 7. why is it 7? // Note that after encoding is set, each length is 1 in both Chinese and English. // A 1 2 AH // 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 = 7 // Is it exactly 7 characters long? Echo mb_strlen ($ str, 'utf8 '); // The same is true for mb_substr. // I only want 5 characters Echo mb_substr ($ str, 0, 5, 'utf8'); // output aa12 In fact, there are a lot of useful functions in the mb extension. I will not list them here. If you are interested, you can view the official manual. Http://www.php.net/manual/zh/ref.mbstring.php Now, we will introduce you here today.