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HomeBackend DevelopmentPHP TutorialPHP string interception function

This article introduces a function that comes with PHP to intercept strings. It can only handle English. Numbers cannot intercept mixed Chinese. Friends in need can refer to it. The latter ones are easier to use. The first one is mainly For beginners to learn.

  //构造字符串  
  $str = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";  
   echo "原字符串:".$str."  
 ";  
   //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."  
 ";  
   $str2 = substr($str,9,4);  
   echo "从第9个字符开始取4个字符:".$str2."  
 ";  
   $str3 = substr($str,-5);  
   echo "取倒数5个字符:".$str3."  
 ";  
   $str4 = substr($str,-8,4);  
   echo "从倒数第8个字符开始向后取4个字符:".$str4."  
 ";  
   $str5 = substr($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."  
 ";  
  ?>

Supports mixed Chinese and English interception.

/* 
------------------------------------------------------ 
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;  
 }  
 ?>


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