In the JavaScript, the variables can
be used before declared, this kinds of mechanism is called
Hoisted. It's a default behavior of JavaScript.
You can easily understanding in the below example in detail.
//The variable
declaration look like.
var emp;
//The variable
initialization look like.
emp = "Anil Singh";
var emp; //The declaration of
emp is hoisted but the value of emp is undefined.
emp = 10; //The Assignment still occurs where we intended (The value of emp is 10)
function getEmp() {
var emp; //The declaration of a
different variable name emp is hoisted but the value of emp is undefined.
console.log(emp); //The output is undefined
emp = 20; //The assignment values is 20.
console.log(emp); //The output is 20.
}
getEmp();
console.log(emp); //The variable named emp in the outer scope still contains 10.
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Anil Singh is an author, tech blogger, and software programmer. Book writing, tech blogging is something do extra and Anil love doing it. For more detail, kindly refer to this link..
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