你好，请问PHP自定义函数如何截取中英文字符串？代码如下：

Question

<?phpheader("content-type:textcml;charset=utf-8");$str="hello这是什么鬼?";function cn_substr($str,$len){for($q=0;$q<$len;$q++){ //循环if(ord(substr($str,$q))>0xa0){ //判断 0xa0=160$tmpstr.=substr($str,$q,3);$q+=3;}else{$tmpstr.=substr($str,$q,1);}return $tmpstr;}echo cn_substr ($str,5);}?>

Answer 1

function cn_substr($str,$len){
for($q=0;$q<$len;$q++){ //循环
if(ord(substr($str,$q))>0xa0){ //判断 0xa0=160
$tmpstr.=substr($str,$q,3);
$q+=3;
}else{
$tmpstr.=substr($str,$q,1);
}
return $tmpstr;
}
}
echo cn_substr ($str,5);//请在函数外调用