Count characters in JavaScript, 2 characters in Chinese characters

The simplest str.length can be, examples

var str = "465464656464566";

var strlength = str.length;

Example 2, JS statistics string in the number of characters, 1 in Chinese 2 characters example:

<input type= "text"  id= "box"  size= " /> <input type=" button " onclick=" Countchar () " value=" Statistical characters  /> <script type= "Text/javascript" > Function countchar ()  { var textobj = document.getelementbyid (' box ');  var text = 
Textobj.value;
 var len = 0;  for  (var i = 0; i < text.length; i++)  {  if   (Text.charcodeat (i)  > 127)  {   len += 2;   } 
else {   len++;   }  }  alert (Len); </script> or regular function getstrlength (str)  {       var carr  = str.match (/[^\x00-\xff]/ig);       return str.length +   (carr == null ? 0 : carr.length);  }

Example 3, distinguishing character encoding

GBK Length calculation function:

 GBK Character Set actual length calculation Function getstrleng (str) {    var realLength = 0;

    var len = str.length;

    var charCode = -1;     for (var i = 0; i < len; i++) {   

     charcode = str.charcodeat (i);         if  (charcode >= 0 &&  charcode <= 128)  {             

 realLength += 1;         }else{               //  if it is Chinese then length plus 2            

 realLength += 2;         }     }&nbsP

    return realLength; }

UTF8 length calculation function:

 utf8 Character Set actual length calculation Function getstrleng (str) {    var realLength = 0;

    var len = str.length;

    var charCode = -1;     for (var i = 0; i < len; i++) {   

     charcode = str.charcodeat (i);         if  (charcode >= 0 &&  charcode <= 128)  {             

 realLength += 1;         }else{               //  if it is Chinese then length plus 3            

 realLength += 3;         }     }&nbSp

    return realLength; }