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JavaScript Object-Oriented JavaScript (2015) Practice Project User Interface Code

Kornel L
Kornel L
4,368 Points
Posted by Kornel L
Kornel L
4,368 Points

Syntax question

displayQuestion: function() { this.populateIdWithHTML("question", quiz.getCurrentQuestion().text); },

I don't understand the : in the syntax, before the function. What is it? Why is it there? Shouldn't it be = ? Can someone explain it please? Thank You!

3 Answers

Michael Braga
.a{fill-rule:evenodd;}techdegree seal-36
Michael Braga
Full Stack JavaScript Techdegree Graduate 24,174 Points

Because we are using an Object Literal (due to the open and end braces)

var objectLiteral = {}; // I am an object literal

we assign our properties and methods with : and not =

var objectLiteral = {
  name: 'Michael',  //property
  greet: function() {  //method
    console.log(this.name);
  }
}

Using an = when assigning a property or method within an Object Literal will produce an error

var objectLiteral = {
  name = 'Michael',  //Error :(
  greet = function() {  //Error :(
    console.log(this.name);
  }
}
Kornel L
Kornel L
4,368 Points
Kornel L
Kornel L
4,368 Points

Thank You for your answers!

edinjusupovic
edinjusupovic
5,664 Points
edinjusupovic
edinjusupovic
5,664 Points

The displayQuestion is an object and inside that, you have an anonymous function (unnamed)

Julio Soto
Julio Soto
4,544 Points
Julio Soto
Julio Soto
4,544 Points

Is JSON. Look it up. that is how you make any object in Javascript.