closure in js
A closure gives you access to an outer function’s scope from an inner function
//example
function init() {
var name = 'Mozilla'; // name is a local variable created by init
function displayName() { // displayName() is the inner function, a closure
alert(name); // use variable declared in the parent function
}
displayName();
}
init();js closure examples
function outer() {
var counter = 0; // Backpack or Closure
function incrementCounter() {
return counter++;
}
return incrementCounter;
}
const count = outer();
count(); // 0
count(); // 1
count(); // 2what is closure in javascript
function OuterFunction() {
var outerVariable = 100;
function InnerFunction() {
alert(outerVariable);
}
return InnerFunction;
}
var innerFunc = OuterFunction();closures in javascript
function OuterFunction() {
var outerVariable = 100;
function InnerFunction() {
alert(outerVariable);
}
return InnerFunction;
}
var innerFunc = OuterFunction();
innerFunc(); // 100es6 closures
var makeCounter = function() {
var privateCounter = 0;
function changeBy(val) {
privateCounter += val;
}
return {
increment: function() {
changeBy(1);
},
decrement: function() {
changeBy(-1);
},
value: function() {
return privateCounter;
}
}
};
var counter1 = makeCounter();
var counter2 = makeCounter();
alert(counter1.value()); /* Alerts 0 */
counter1.increment();
counter1.increment();
alert(counter1.value()); /* Alerts 2 */
counter1.decrement();
alert(counter1.value()); /* Alerts 1 */
alert(counter2.value()); /* Alerts 0 */What is Closures in JavaScript
/*A closure is the combination of a function bundled together (enclosed) with references
to its surrounding state (the lexical environment). In other words, a closure gives you
access to an outer function’s scope from an inner function. In JavaScript, closures are
created every time a function is created, at function creation time.*/
function init() {
var name = 'Mozilla'; // name is a local variable created by init
function displayName() { // displayName() is the inner function, a closure
alert(name); // use variable declared in the parent function
}
displayName();
}
init();Copyright © 2021 Codeinu
Forgot your account's password or having trouble logging into your Account? Don't worry, we'll help you to get back your account. Enter your email address and we'll send you a recovery link to reset your password. If you are experiencing problems resetting your password contact us
