Five methods for determining the string length in JS

This article mainly introduces five methods for determining the string length in JS and distinguishes Chinese and English. For more information, see

Objective: To calculate the String length (1 character in English and 2 Characters in Chinese) Method 1: the code is as follows: String. prototype. gblen = function () {var len = 0; for (var I = 0; I <this. length; I ++) {if (this. charCodeAt (I)> 127 | this. charCodeAt (I) = 94) {len + = 2;} else {len ++;} return len;} Method 2: the code is as follows: function strlen (str) {var len = 0; for (var I = 0; I <str. length; I ++) {var c = str. charCodeAt (I); // Add 1 if (c> = 0x0001 & c <= 0x007e) to a single byte | (0xff60 <= c & c <= 0xff9f) {Len ++;} else {len + = 2 ;}} return len ;}method 3: Code: var jmz ={}; jmz. getLength = function (str) {// <summary> obtain the actual length of the string, which is 2 in Chinese, english 1 </summary> // <param name = "str"> string to be obtained </param> var realLength = 0, len = str. length, charCode =-1; for (var I = 0; I <len; I ++) {charCode = str. charCodeAt (I); if (charCode> = 0 & charCode <= 128) realLength + = 1; else realLength + = 2;} return realLength ;}; Method 4: Code Var l = str. length; var blen = 0; for (I = 0; I <l; I ++) {if (str. charCodeAt (I) & 0xff00 )! = 0) {blen ++;} Method 5: Replace the dual-byte with two single-byte values and obtain the Length Code as follows: getBLen = function (str) {if (str = null) return 0; if (typeof str! = "String") {str + = "";} return str. replace (/[^ \ x00-\ xff]/g, "01"). length ;}