difference between const and var in javascript code example
Example 1: what is the difference between let and const in javascript
The difference is that with const you can only only assign a value to a variable
once, but with let it allows you to reassign after it has been assigned.
Example 2: var or const in javascript
// var declares a variable, meaning its value will vary.
// const declares a constant, meaning its value will remain
// consistant and not change.
// If your variable changes throughout the program or website,
// declare it using a var statement.
// Otherwise, if its value does not change, declare it using
// a const statement.
const myConst='A const does not change.';
var myVar='A var does change.';
var myVar=2;
Example 3: difference between var let and const in javascript with example
//functional scope
var a; // declaration
a=10; // initialization;
//global scope
// re-initialization possible
let a;//only blocked scope & re-initialization possible
a=10;
let a =20;
if(true){
let b =30;
}
console.log(b); // b is not defined
const // const also blocked scope,Re-initialization and re-declaration not possible
const a; // throws error {when we declaring the value we should assign the value.
const a =20;
if(true){
const b =30;
}
console.log(b); // b is not defined
console.log(a); // no output here because code execution break at leve b.