Skip to main content

Immediately Invoked Function Expression (IIFE) in Javascript with Example

Example of Immediately Invoked Function Expression (IIFE) in Javascript
Run this code here: https://repl.it/@VinitKhandelwal/iife
(function () {
  function Question(q,a,c) {
    this.q = q;
    this.a = a;
    this.c = c;
  }

  Question.prototype.displayQuestion = function() {
    console.log(this.q);
    for (var i = 0; i < this.a.length; i++) {
      console.log(i+": "+this.a[i]);
    }
  }

  Question.prototype.checkAnswer = function(ans) {
    if (ans===this.c) {
      console.log("correct");
    } else {
      console.log("incorrect");
    }
  }

  var q1 = new Question('Is Javascript the coolest?', ['yes', 'no'], 0);
  var q2 = new Question('Is python better than Javascript?', ['yes', 'no', 'both are same'], 2);
  var q3 = new Question('Is Javascript the worst?', ['yes', 'no'], 1);

  var questions = [q1, q2, q3];

  var n = Math.floor(Math.random() * questions.length)

  var answer = parseInt(prompt(questions[n].displayQuestion()));
  questions[n].checkAnswer(answer);
})();

Comments

Popular posts from this blog

Difference between .exec() and .execPopulate() in Mongoose?

Here I answer what is the difference between .exec() and .execPopulate() in Mongoose? .exec() is used with a query while .execPopulate() is used with a document Syntax for .exec() is as follows: Model.query() . populate ( 'field' ) . exec () // returns promise . then ( function ( document ) { console . log ( document ); }); Syntax for .execPopulate() is as follows: fetchedDocument . populate ( 'field' ) . execPopulate () // returns promise . then ( function ( document ) { console . log ( document ); }); When working with individual document use .execPopulate(), for model query use .exec(). Both returns a promise. One can do without .exec() or .execPopulate() but then has to pass a callback in populate.

Two Ways of rendering in React Examples

Two Ways of rendering in React Examples 1 - Render twice HTML < div id = "p1" ></ div > < div id = "p2" ></ div > CSS . person { display : inline - block ; margin : 10px ; border : 1px solid # eee ; box - shadow : 0 2px 2px # ccc ; } JAVASCRIPT (Babel) function Person ( props ) { return ( < div className = ' person "> < h1 >{ props . name }</ h1 > < p > Age :{ props . age }</ p > </ div > ); } ReactDOM . render (< Person name = "VK" age = "29" />, document . querySselector ( '#p1' )); ReactDOM . render (< Person name = "HK" age = "28" />, document . querySselector ( '#p2' )); 2 Render all at once HTML < div id = "app" ></ div > CSS . person { display : inline - block ; margin : 1...

Resolve: Uncaught TypeError: firebase.database is not a function

If you are getting the error: Uncaught TypeError: firebase.database is not a function Resolve it by including firebase-database.js in your html page as follows: <!-- The core Firebase JS SDK is always required and must be listed first --> <script defer src = "https://www.gstatic.com/firebasejs/6.2.4/firebase-app.js" ></script> <script defer src = "https://www.gstatic.com/firebasejs/3.1.0/firebase-database.js" ></script> That is it. Let me know if this was helpful.