php切り取り文字列
10146 ワード
1 /**
2 * - -【 】
3 * @param string $string
4 * @param int $length
5 * @param string $dot ...
6 * @param string $charset
7 * @return string
8 */
9 public function cutstr($string, $length, $dot = ' ...', $charset = 'utf-8') {
10 if (strlen($string) <= $length) {
11 return $string;
12 }
13 $string = str_replace(array('&', '"', '<', '>'), array('&', '"', '<', '>'), $string);
14 $strcut = '';
15 if (strtolower($charset) == 'utf-8') {
16 $n = $tn = $noc = 0;
17 while ($n < strlen($string)) {
18 $t = ord($string[$n]); //ASCIIֵ
19 if($t == 9 || $t == 10 || (32 <= $t && $t <= 126)) {
20 $tn = 1; $n++; $noc++;
21 } elseif (194 <= $t && $t <= 223) {
22 $tn = 2; $n += 2; $noc += 2;
23 } elseif (224 <= $t && $t < 239) {
24 $tn = 3; $n += 3; $noc += 2;
25 } elseif (240 <= $t && $t <= 247) {
26 $tn = 4; $n += 4; $noc += 2;
27 } elseif (248 <= $t && $t <= 251) {
28 $tn = 5; $n += 5; $noc += 2;
29 } elseif ($t == 252 || $t == 253) {
30 $tn = 6; $n += 6; $noc += 2;
31 } else {
32 $n++;
33 }
34 if($noc >= $length) {
35 break;
36 }
37 }
38 if ($noc > $length) {
39 $n -= $tn;
40 }
41 $strcut = substr($string, 0, $n);
42 } else {
43 for ($i = 0; $i < $length; $i++) {
44 $strcut .= ord($string[$i]) > 127 ? $string[$i].$string[++$i] : $string[$i];
45 }
46 }
47 $strcut = str_replace(array('&', '"', '<', '>'), array('&', '"', '<', '>'), $strcut);
48 return $strcut.$dot;
49 }