php教程 截取一定长度的字符串（该函数对gb2312使用有效

function ssubstr($string, $length, $dot = ' ...') {
	 global $charset;
	  if(strlen($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[$n]);
	     if($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;
	}
	 
	截取一定长度的字符串（该函数对gb2312使用有效） 
	function wordscut($string, $length ,$sss=0) {
	if(strlen($string) > $length) {
	               if($sss){
	$length=$length - 3;
	$addstr=@# ...@#;
	}
	  for($i = 0; $i < $length; $i++) {
	   if(ord($string[$i]) > 127) {
	$wordscut .= $string[$i].$string[$i + 1]; //
	$i++;
	   } else {
	$wordscut .= $string[$i];
	   }
	  }
	  return $wordscut.$addstr;
	}
	return $string;
	}
	?>

教程链接:http://www.phprm.com/function/php1004606.html

随意转载~但请保留教程地址★