JavaScript02/closure.html at main · AaminSingh/JavaScript02 · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Closure</title>
</head>
<body style="background-color: #3232;">
    <button id = "orange">Orange</button>
    <button id = "green">Green</button>

</body>
<script>
    // closure
    /*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 a function access to its outer scope. In JavaScript, closures are
    created every time a function is created, at function creation time.*/


   /* function init() {
        let name = "Mozilla";  // name is a local variable created by init
        function displayName() {
                               // displayName() is the inner function, that forms a closure
            console.log(name); // use variable declared in the parent function
  }
        displayName();
}
        init();*/


       /** function outer(){
            let username = "hitesh"
            console.log("Outer", secret)
            function inner(){
                let secret = "my2428"                        // no sharing between the inner fxn
                console.log("inner", username);
            }
            function innerTwo(){
                console.log("innerTwo", username);
            }
            inner()
        }
        outer()
        console.log(username);
*/

/*function makeFunc() {
  const name = "Mozilla";
  function displayName() {
    console.log(name);
  }
  return displayName;                                //here the inner fxn is returned
}
const myFunc = makeFunc();                          // this function is the reference of the displayname() so as it has lexical scoping it will also carry the scope of its outer fxn
myFunc();*/
</script>
<script>
           document.getElementById("orange").onclick = function(){
            document.body.style.backgroundColor = `orange`
           }
           document.getElementById("green").onclick = function(){
            document.body.style.backgroundColor = `green`
           }
</script>
</html>