pem scope

has been a bit confused on the scope of JS, today by chance to read JavaScript authoritative guide, immediately be attracted to, write really good. I look at the sixth version, quite thick, about 1000 pages, JS Broad and profound, to be familiar with the need to master the great perseverance of Kung Fu.One: function scopeLet's look at a short piece of code:[JavaScript]View Plaincopy var scope="glob

The scope of JS has been a bit confused, and today I accidentally read the JavaScript Authority Guide, was immediately attracted to write really good. I am looking at the sixth version, quite thick, probably more than 1000 pages, JS Broad and profound, to be familiar with the need to master the great perseverance great effort. One: function scopes First look at a small piece of code: var scope= "global"; fu

In AngularJS, you sometimes need to monitor a variable in Scope, because the variable changes will affect the display of some interface elements, next, we will use this article to introduce AngularJS to monitor Scope variables and call Scope Methods externally. For more information, see AngularJS. Sometimes you need to monitor a variable in

In Angularjs, it is sometimes necessary to monitor a variable in scope because changes in variables affect the display of some interface elements. Sometimes, you also want to invoke a method of scope through jquery. For example, the following scenario: Above, we hope: Jqbtnstate variable value in scope if False let the button with ID jqbtn disable

Javascript scope and JS Scope After reading this article, I found that the more basic things are displayed, the more advanced they are.Reference: http://realazy.org/blog/2007/07/18/scope-in-javascript/Scope is one of the cornerstones of the Javascript language. It may also be the most headache for me when building comp

Scope in a functionThe so-called function scope, that is, all the variables that belong to this function can be used and reused throughout the scope of the function.1 function foo (a) {2 var b=a;3 function Bar (c) {4 var c=b*2;5 Console.log (c); 6 }7 Bar (); }9 foo (3);1 function foo (a) {2

Scope in a functionThe so-called function scope, that is, all the variables that belong to this function can be used and reused throughout the scope of the function. 1 function foo (a) { 2 v AR b=A; 3 function Bar (c) { 4 var c=b*2; 5 Console.log (c); 6 } 7 Bar (); // 4 8 } 9 foo (3); 1 functionFoo (a) {2 varb=A;3 functio

Scope rules that are common in development languages have block-level scopes and lexical scopesThe scope in which the scope can function is defined by its name, which is the area that defines a variable.Block-level scope is to use a block structure to partition the variable access area block that {} represents the lang

I believe that many beginners in JavaScript and the execution environment and scope chain can not be very good understanding, here, I will follow their own understanding to share with you. In general, we divide the execution environment into global execution environment and local execution environment, in which local execution environment can be called function execution environment. So what exactly makes the execution environment? In layman's parlan

var i = 2,x = 5;var fn = function (x) {x + = 3;return function (y) {Console.log (x + +) + y + (--);}};var f = fn (1);F (2);FN (3) (4);F (5);Answer: F (2) = 7; FN (3) (4) = 10; F (5) =>9;Problem Solving Ideas:1. var f = fn (1); equivalent to opening a heap of memory (private scope), parameter assignment. Top-down execution, x assignment is 4;2. F (2) performs a return function (y) parameter assignment, function (y) opens up a heap of memory, X does no

JS Scope and scope chainhttp://blog.csdn.net/yueguanghaidao/article/details/9568071One: function scopeThe first sentence output is: "Undefined", not "global"The second output is: "Local"You might think that the first sentence will output: "Global" because the code has not executed var scope= "local", so it will definitely output "global".I said the idea was absol

I. Description of scopeThere is an incisive description of scopes in the JavaScript authoritative guide: "The functions in JavaScript run in their defined scopes, not in the scopes they are executed in." ”In JavaScript, the concept of scopes is almost the same as in other languages, and each time a function is called, it enters a scope within a function, and when returned from the function, returns the scope