Commonly used functions for processing strings in PHP Chinese and English mixed typesetting_PHP tutorial

# Determine whether a certain position is the left or right half of a Chinese character, or not Chinese
# Return value -1 Left 0 Not a Chinese character 1 Right
# Usage
/*
$a = ' this is 中文';
print is_chinese($a, 1); // 0
print is_chinese($a,8); // -1
print is_chinese($a,9); // 1
*/
function is_chinese(&$str, $location) {
$ch = true;
$i = $location;
while(ord($str[$i] )>0xa0 && $i >= 0) {
$ch = !$ch;
$i --;
}

if($i != $location) {
$f_str = $ch ? 1: -1;
}
else {
$f_str = false;
}

return $f_str;
}


# Chinese string inversion function
# If a string with Chinese characters is reversed using strrev, garbled code will be generated
/*
print cstrrev('this is Chinese'); // In the text si siht
*/

function cstrrev(&$str) {
$long = strlen($str);
for($f_str=' ', $chinese=false, $i=$long-1; $i>=0; $i--) {
if(ord($str[$i]) > 0xa0) {
$ chinese = ! $chinese;
if($chinese == false) {
$f_str .= $str[$i].$str[$i+1];
}
}
else {
$f_str .= $str[$i];
}
}
return $f_str;
}
/* Chinese string interception function
Some Chinese string interception functions often have some problems, such as in some automatic line wrapping programs
$a="1 in 2";
After intercepting twice,
csubstr($str,$a, 0,2);
csubstr($str, $a, 2,2)
Since the loading position points to the right byte of "middle", the result may be like this
1, 2
Using this function will produce the correct result
1, 2
*/
# start starting position, starting from 0
# long = 0, then take from start to the end of the string
# When ltor = true, characters are taken from left to right, when false, characters are taken from right to left.
# $cn_len Chinese characters are taken by byte or number of words. If they are taken by word number, one Chinese character is counted as one byte.

function csubstr(&$str, $start=0, $long=0, $ltor=true, $cn_len=2) {
if($long == 0) $long = strlen( $str);
if($ltor == false) $str = cstrrev($str);

if($cn_len == 1) {

for($i= 0, $fs=0; $i<$start; $fs++)
$i += (ord($str[$fs]) <= 0xa0) ? 1 : 0.5;
for($i =0, $fe=$fs; $i<$long; $fe++)
$i += (ord($str[$fe]) <= 0xa0) ? 1 : 0.5;
$long = $fe - $fs;

}
else {

$fs = (is_chinese($str, $start) == 1) ? $start - 1 : $start;
$fe = $long + $start - 1;
$end = ( is_chinese($str, $fe) == -1 ) ? $fe -1 : $fe;
$long = $ end - $fs + 1;
}

$f_str = substr($str, $fs, $long);
if($ltor == false) $f_str = cstrrev($f_str ; bytes
function cleft(&$str, $long, $cn_len=2) {
$f_str = csubstr($str, 0, $long, true, $cn_len);
return $f_str ;
}

# Get the right string
function cright(&$str, $long, $cn_len=2) {
$f_str = cstrrev($str);
$f_str = csubstr($f_str, 0, $long, true, $cn_len);
$f_str = cstrrev($f_str);
return $f_str;
}
# Pairs containing Chinese characters Format articles in separate lines
# No more problems caused by line breaks! ! !
# Note: Each line of the article must be separated by n (chr(13))
# $width How many characters per line
# $br What character should be used as the end character for each line

function ctext_wrap(&$text, $width=60, $br="
") {
$lines = explode("n",$text);
$rows = count($ lines);

for($i=0; $i<$rows; $i++) {
$len = strlen($lines[$i]);
for($j= 0; $j<$len; $j+=$width) {
$p = $j + $width - 1;
$k = 0;
if($p<$len) {
while(!is_chinese($lines[$i], $p) && $lines[$i][$p] != ' ' && $p>$j) {
$k ++;
$p --;
}
if($p == $j) $k = 0;
}
$f_str .= csubstr($lines[$i], $j, $width-$k) . $br;
$j -= $k;
}
}
return $f_str;
}