javascript string concatenation operator

I recently read "Advanced guide for high-performance website construction", Chapter 7 is "Writing efficient JavaScript", and the author is Nicholas C. zakas (also author of JavaScript advanced programming) describes the optimization of string connections. String connection is always one of the operations with the lowes

lengthThe Length property can return the number of characters in a string.Length is obtained based on the UTF-16 encoding of the string, with an empty string length of 0. Length cannot be modified.charAt ()The CharAt () method returns the character at the specified position. Note that JavaScript does not have a character data type that differs from the

String object String object is used to process text (String ).Syntax for creating a String object: new String(s);String(s);Parameters ParametersSIs the value to be stored in the String

False, zero, null, undefined, and empty string objects in Javascript In Javascript, We often come into contact with the five special objects mentioned in the question -- false, 0, empty string, NullAnd undefined. These objects are easy to use incorrectly, so you must be careful when using them. Type Detection Let'

string object, if there is no match, returns -1,SUBSTR as the specified substring, startindex the integer value that indicates the start index position within the string object to find. If omitted, the lookup starts at the end of the string.var a= "ABCDEFGB"; Alert (A.lastindexof ("B")); 7　　9, concat ()Returns a string that contains the

A string is defined in JavaScript by double or single quotation marks. the string object has only one property: The length property , which gets the lengths of the strings. Methods for handling the string itselfCharAt (Index)Returns a character at the specified position of index in the

Method of String 1. String: The contents of the enclosed or double quotation marks in JS are strings;var t = "true"; Console.log (typeof T); // "string"Console.log (typeoftrue); // "Boolean" var str = "Yyy./niha"; var s = ' www '; var str = "HelloWorld";2. Index: In the string, each character has a corresponding index,

There is no StringBuffer class in JavaScript when the situation is displayed, and a mainstream JavaScript StringBuffer class is implemented by prototype to construct a StringBuffer class. Stringbuffer.js Copy Code code as follows: function StringBuffer () { This.content = new Array; } StringBuffer.prototype.append = function (str) { This.content.push (str); } StringBuffer.proto

string immutable, JS and no similar method. But we can simulate this buffer mechanism. The principle is to use an array of stitching, the source code is as follows: Copy Code code as follows: function StringBuffer () { this.__strings__ = new Array (); } StringBuffer.prototype.append = function (str) { This.__strings__.push (str); return this; Convenient chain operation } StringBuffer.prototype.toString = function () {

In JavaScript, we are often exposed to the 5 more special objects mentioned in the topic--false, 0, empty strings, null, and undefined. These objects are easy to use, so you have to be careful when you use them.Type detectionLet's come down and see what their type is:[HTML]View Plaincopyprint? script Type= "Text/javascript" > alert (typeof (false) = = = ' Boolean '); Alert (typ

item to the array (replace the deleted item)String properties:str.length; view string length;String method:Str.charat (index); Gets the corresponding character according to index;Str.concat (str2); concatenation of strings;Str.indexof (); Finds the first occurrence of a character subscript;Str.lastindexof (); Finds th

() method is invoked. At this point, the following steps are performed: (1) Create a string that stores the results. (2) Copy each string to the appropriate location in the result. Copy Code code as follows: function StringBuilder () { This._string=new Array (); } Stringbuilder.prototype.append=function (str) { This._string.push (str); } Stringbuilder.prototype.tostring=function

be manipulated like an array:You can also manipulate strings directly:If the value inside [] is not a number, or is out of range, or uses a letter:The string is similar to an array, and the string is an array-like object that cannot change a single character within a string. The string also cannot add a new property.A

Coding problem in JSHttps://www.haorooms.com/post/js_escape_encodeURIComponentI in the front-end JS Add time to create the DOM, there are Chinese characters, found to be garbled on the study of the nextFor character encoding javascript:escape("\u6625\u8282");//输出 "%u6625%u8282" javascript:unescape("%u6625%u8282");//输出 "春节" javascript:unescape("\u6625\u8282");//输出 "春节"For URL Chinese character codingencodeURIComponent()相比encodeURI()要更加彻底。decodeURI()JS string