javascript concatenate variables

, and this pointer points to an object stored in the heap. When the copy is complete, the two variables point to the same object in the heap, so changing one of the values will have an effect on the other. Has the following codevar obj1 = new Object (); var obj2 = obj1; Obj1.name = "Nicholas"; alert (obj2.name); "Nicholas"So the above code executes the process as follows:Passing parametersIn JavaScript, th

environment, it continues to search up the scope chain. The search process goes back to the variable object of the global environment. If the identifier is not found in the global environment, it means that the variable is not yet declared.11. The principle of garbage collection: Identify variables that are no longer in use, and then release the memory they occupy. To do this, the garbage collector periodically performs this operation at a fixed time

Details about global variables in the Javascript framework This article describes global variables and simple code in the Javascript framework. We hope that this article will give you a new understanding of global variables. For the

= b-a;But feelings and forms are easier to understand.Exchange Variable Value Scheme IIIThis method for the first time to learn JavaScript may not understand, because our JavaScript is rarely used in place, this is what I learned before the algorithm contest book, through the underlying bit operation to exchange variable values, is the above scheme evolvedA ^= b;//or b ^= a;a ^= b;Know that C + + can even

Please visit http://www.cnblogs.com/rubylouvre/archive/2009/08/21/1551270.html in the original,I was just trying to make a record.Scope of JavaScript variablesWhy the first alert is undefined, and the second one is true. This problem can also be extended to--alert (b) When the external B is found, and alert (a) will not go outside to find?!We all know that the precedence of local variables is greater than g

Original: Learn JavaScript from the beginning (ii)--variables and their scopesOne, variableECMAScript variables are loose variables, so-called loose variables, that is, variable names can hold any type of data, each variable is just a placeholder for holding the value.Defini

One, variableJavascript has five basic data types number, String, boolean, undefined, null a composite type: ObjectSecond, using the getElementById method to obtain the elementWay One:Here the element, refers to the HTML tag, through the built-in docuement ' getElementById ' method to get the element that set the id attribute on the page, get an HTML object, and assign a value to it,Do not assign a value to see an example:DOCTYPE HTML>HTMLLang= "en">Head> Scripttype= "Text/

Unlike programming languages such as C and Java, variables in JavaScript are of no type, and all variables are defined with the following keywords var: Copy Code code as follows: var A; var m, N; var x=42, y= "test"; If the variable is not assigned after the variable is defined, the value of the variable is undefined. The values for

This article mainly introduces JavaScript variables and data types. It is the basic knowledge in getting started with JavaScript. If you need JavaScript data types, refer: One of the most fundamental features of a programming language is a set of data types it supports. These are the types of values that can be expres

DOCTYPE HTML>HTML>HeadLang= "en"> MetaCharSet= "Utf-8"/> title>title> Scriptsrc=".. /js/jquery-1.10.2.js ">Script> Script>//1 I output global variables for global variables functionMyName () {i= 'Global Variables'; } myName (); functionSayname () {alert (i); } sayname ();//2 I run error for local variable display i undefined funct

, but written as a separate JS file is conducive to the separation of structure and behavior.4, cross-platform features, under the support of most browsers, can be run on a variety of platforms (such as Windows, Linux, Mac, Android, iOS, etc.) Basic syntax (variables, expressions, scopes, various keywords, and process Control statements)Cond...What is the JavaScript language, its history, its function