Chinese interception without garbled characters (2 methods)

Chinese interception without garbled characters (2 methods)

//$str The string to be intercepted
//$len The number of characters to be intercepted
//$chars The number of characters that have been intercepted
//$res The saved string
// $chars stores the number of intercepted strings
//$offset is the intercepted offset
//$length is the number of bytes of the string
//If $len>the number of characters in $str, it will cause a unnecessary while loop , ($offset<$length limit)
function utf8sub($str,$len){
 if($len<=0){
 return ;
 }
 $res="";
 $offset=0;
 $ chars=0;
 $length=strlen($str);
 while($chars<$len && $offset<$length){

 $hign=decbin(ord(substr($str,$offset,1)) );
 if(strlen($hign)<8){
 $count=1;
 }elseif(substr($hign,0,3)=="110"){
 $count=2;
 }elseif (substr($hign,0,4)=="1110"){
 $count=3;
 }elseif(substr($hign,0,5)=="11110"){
 $count=4;
 }elseif(substr($hign,0,6)=="111110"){
 $count=5;
 }elseif(substr($hign,0,7)=="1111110"){
 $count=6 ;
 }

 $res.=substr($str,$offset,$count);
 $offset+=$count;
 $chars+=1;


 }
 return $res;
}
function utf8sub1($ str,$len){
 $chars=0;
 $res="";
 $offset=0;
 $length=strlen($str);
 while($chars<$len && $offset<$length) {
 $hign=decbin(ord(substr($str,$offset,1)));
 if(strlen($hign)<8){
 $count=1;
 }elseif($hign & "11100000 "=="11000000"){
 $count=2;
 }elseif($hign & "11110000"=="11100000"){
 $count=3;
 }elseif($hign & "11111000"==" 11110000"){
 $count=4;
 }elseif($hign & "11111100"=="11111000"){
 $count=5;
 }elseif($hign & "11111110"=="11111100"){
 $count=6;
 }
 $res.=substr($str,$offset,$count);
 $chars++;
 $offset+=$count;
 }
 return $res;
}
$a="中华ah人hdj";
echo utf8sub($a,5);
?>