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JavaScript JavaScript Foundations Objects Prototypes

sergio verdeza
PLUS
sergio verdeza
Courses Plus Student 10,765 Points
Posted by sergio verdeza
sergio verdeza
Courses Plus Student 10,765 Points

Modify the Car's prototype to have 'wheels' set to 4. Hello, having trouble with this question? Help.......

var carPrototype = { model: "generic", currentGear: 0,

increaseGear: function() {
  this.currentGear ++;
},
decreaseGear: function() {
  this.currentGear--;
}

}

function Car (model) { this.model = model; }

Car.prototype = carPrototype;

Car.prototype.wheels = 4

index.html 
<!DOCTYPE html>
<html lang="en">
  <head>
    <title> JavaScript Foundations: Objects</title>
    <style>
      html {
        background: #FAFAFA;
        font-family: sans-serif;
      }
    </style>
  </head>
  <body>
    <h1>JavaScript Foundations</h1>
    <h2>Objects: Prototypes</h2>
    <script>


      var carPrototype = {
        model: "generic",
        currentGear: 0,
        wheels: 4,
        increaseGear: function() {
          this.currentGear ++;
        },
        decreaseGear: function() {
          this.currentGear--;
        } 
      }

      function Car(model) { this.model = model; }

       Car.prototype.wheels = 4;




    </script>
  </body>
</html>

2 Answers

Madeleine Nyhagen
Madeleine Nyhagen
2,880 Points
Madeleine Nyhagen
Madeleine Nyhagen
2,880 Points

I think you are just doing too much. I was successful using Car.prototype.wheels = 4; but did not add anything directly to the carPrototype variable. I believe my code looked like this:

var carPrototype = {
        model: "generic",
        currentGear: 0,
        increaseGear: function() {
          this.currentGear ++;
        },
        decreaseGear: function() {
          this.currentGear--;
        } 
      }

      function Car(model) {
        this.model = model;
      }

      Car.prototype = carPrototype;
      Car.prototype.wheels = 4;
chris slaats
chris slaats
5,996 Points
chris slaats
chris slaats
5,996 Points

For this question you don't have to use Car.prototype.wheels = 4; because you have set the Car.prototype = carPrototype already. Then all the question is asking is of you is to change the Car's prototype which you have just set to carPorotypes variable wheels to 4 so it should look like this. Hope that helps

var carPrototype = {
        model: "generic",
        currentGear: 0,
        wheels: 4,
        increaseGear: function() {
          this.currentGear ++;
        },
        decreaseGear: function() {
          this.currentGear--;
        } 
      }

      function Car(model) {
        this.model = model;
      }

      Car.prototype = carPrototype;