How can you iterate over all properties of an object?
A). for (var key of object)
B). for (var key in object)
C). for (var key with object)
D). for (var key over object)
Which of the following is the correct way to delete a property from an object?
A). remove object.property;
B). delete object.property;
C). delete object[property];
D). object.property = null;
How do you define a method in a constructor function?
A). this.methodName = function() {}
B). this.methodName: function() {}
C). this.methodName = () {}
D). this.methodName: () {}
How do you add a new property to an existing object in JavaScript?
A). object.property = value;
B). object->property = value;
C). object:property = value;
D). object.addProperty('property', value);
What is the purpose of the this keyword in an object method?
A). It refers to the global object.
B). It refers to the current object.
C). It refers to the parent object.
D). It refers to the previous object.
How do you define a constructor function for a Car object?
A). function Car(make, model, year) { this.make = make; this.model = model; this.year = year; }
B). Car(make, model, year) { this.make = make; this.model = model; this.year = year; }
C). function create Car(make, model, year) { this.make = make; this.model = model; this.year = year; }
D). function construct Car(make, model, year) { this.make = make; this.model = model; this.year = year; }
What does Object.keys(obj) return?
A). An array of the values of the object's properties
B). An array of the names of the object's properties
C). The first key of the object
D). The number of properties in the object
How do you create a method inside an object using an object literal?
A). methodName: function() {}
B). methodName = function() {}
C). methodName: () {}
D). methodName: method() {}
Which of the following correctly creates an instance of a Car object using a constructor function?
A). var myCar = Car('Toyota', 'Corolla', 2020);
B). var myCar = new Car('Toyota', 'Corolla', 2020);
C). var myCar = create Car('Toyota', 'Corolla', 2020);
D). var myCar = construct Car('Toyota', 'Corolla', 2020);
How do you define a class in JavaScript ES6?
A). class ClassName { constructor() {} }
B). function ClassName() { constructor() {} }
C). class ClassName() { constructor {} }
D). function class ClassName { constructor() {} }