-
- /**
- * 方法库-截取字符串
- * @param string $string 字符串
- * @param int$length 字符长度
- * @param string $dot 截取后是否添加...
- * @param string $charset编码
- * @return string
- */
- public function cutstr($string, $length, $dot = ' ...', $charset = 'utf-8') {
- if (strlen($string) <= $length) {
- return $string;
- }
- $string = str_replace(array('&', '"', '<', '>'), array('&', '"', '<', '>'), $string);
- $strcut = '';
- if (strtolower($charset) == 'utf-8') {
- $n = $tn = $noc = 0;
- while ($n < strlen($string)) {
- $t = ord($string[$n]); //ASCII?
- if($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];
- }
- }
- $strcut = str_replace(array('&', '"', '<', '>'), array('&', '"', '<', '>'), $strcut);
- return $strcut.$dot;
- }
例2，php检测字符串是否存在：
-
- /**
- * 方法库-字符串是否存在
- * @param string $str :字符或字符串
- * @param string $string :字符串
- * @return string 例子: $str='34' $string='1234' 返回 TRUE
- */
- public function is_str_exist($str, $string) {
- $string = (string) $string;
- $str = (string) $str;
- return strstr($string,$str)===false ? false : true;
- }
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