本文實例講述了php源碼分析之DZX1.5字符串截斷函數cutstr用法。分享給大家供大家參考。具體分析如下：

<?php

/**

* 函數來源DZX1.5，文件所在 /source/function/function_core.php

*/

define('CHARSET','UTF-8');

function cutstr($string, $length, $dot="...") {

if(strlen($string)<=$length) {

return $string;

}

if(strtolower(CHARSET) == "utf-8") {

$n = $tn = $noc = 0;

while($n < strlen($string)) {

$t = ord($string[$n]);

if($t == 9 || $t == 10 || (32 <= $t && $t <= 126)) {

$tn = 1; $n++; $noc++;

} elseif(194 <= $t && $t <= 223) {

$tn = 2; $n += 2; $noc += 2;

} elseif(224 <= $t && $t <= 239) {

$tn = 3; $n += 3; $noc += 2;

} elseif(240 <= $t && $t <= 247) {

$tn = 4; $n += 4; $noc += 2;

} elseif(248 <= $t && $t <= 251) {

$tn = 5; $n += 5; $noc += 2;

} elseif($t == 252 || $t == 253) {

$tn = 6; $n += 6; $noc += 2;

} else {

$n++;

}

if($noc >= $length) {

break;

}

}

if($noc > $length) {

$n -= $tn;

}

$strcut = substr($string, 0, $n);

} else {

for($i = 0; $i < $length; $i++) {

$strcut .= ord($string[$i])>127 ? $string[$i].$string[++$i] : $string[$i];

}

}

$pos = strrpos($strcut, chr(1));

if($pos !== false) {

$strcut = substr($strcut,0,$pos);

}

return $strcut.$dot;

}

$string = '測試數據庫ablci102020@(#)!)!測試勞動力ddk';

echo cutstr($string,15);

/*End of php*/

運行結果如下：

測試數據庫ablci1020...

希望本文所述對大家的php程序設計有所幫助。