The function that comes with PHP to intercept strings can only handle English. Numbers cannot intercept mixed Chinese characters. The latter example is easier to use. The first one is mainly for beginners to learn. The specific The code is as follows:
<?php //构造字符串 $str = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; echo "原字符串:<b>".$str."</b><br>"; //按各种方式进行截取 $str1 = substr($str,5); echo "从第5个字符开始取至最后:".$str1."<br>"; $str2 = substr($str,9,4); echo "从第9个字符开始取4个字符:".$str2."<br>"; $str3 = substr($str,-5); echo "取倒数5个字符:".$str3."<br>"; $str4 = substr($str,-8,4); echo "从倒数第8个字符开始向后取4个字符:".$str4."<br>"; $str5 = substr($str,-8,-2); echo "从倒数第8个字符开始取到倒数第2个字符为止:".$str5."<br>"; ?>
supports mixed Chinese and English interception, the code is as follows:
<?php /* ------------------------------------------------------ 参数: $str_cut 需要截断的字符串 $length 允许字符串显示的最大长度 程序功能:截取全角和半角(汉字和英文)混合的字符串以避免乱码 ------------------------------------------------------ */ function substr_cut($str_cut,$length) { if ( strlen ($str_cut) > $length) { for($i=0; $i < $length; $i++) if (ord($str_cut[$i]) > 128) $i++; $str_cut = substr($str_cut,0,$i).".."; } return $str_cut; } ?>
The above is the detailed content of PHP string interception function usage. For more information, please follow other related articles on the PHP Chinese website!

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