Javascript MCQ Quiz

Javascript is an _______ language?

• statically typed and

  scripting

• statically typed and programming

• dynamically typed and

  programming

• dynamically typed and scripting

How can we make the complete object readonly which will not allow to add/delete/update any properties in the object,

• Object.freeze(ObjectName)

• Object.seal(ObjectName)

• All of the above

• Object.defineProperty(obj, 'readOnlyProperty',
  {

  value: 'somevalue',

  writable: false,

  configurable: true,

  enumerable: false

  
  });

When the switch statement matches the expression with the given labels, how is the comparison done?

• None of the above

• Only the value of the expression is compared.

• Only the datatype of the expression is compared.

• Both the datatype and the result of the expression are compared.

What will be the output of the following code snippet?

<script type="text/javascript">

a = 5 + "9";

document.write(a);

</script>

• Compilation Error

• 14

• 59

• Run time error

When an operator’s value is NULL, the typeof returned by the unary operator is:

const a = null

console.log(typeof(a))

• Boolean

• Undefined

• Object

• Integer

What will be the output of the following code snippet?

var a = true + true + true * 5;

print(a)

• 7

• 6

• 5

• 15

What is the output of the following code snippet?

print(NaN === NaN);

• True

• False

• undefined

• error

Which function is used to serialize an object into a JSON string in Javascript?

• stringify()

• parse()

• toString()

• None of the above

What will be the output of the following code snippet?

const obj1 = {Name: "Hello", Age: 16};

const obj2 = {Name: "Hello", Age: 16};

print(obj1 == obj2)

• True

• False

• Undefined

• None

const person = { name: 'John', age: 30, };

const newPerson = person;

person.name = 'Mehul';

console.log(newPerson);
console.log(person)

• newPerson:
  { name: 'John', age: 30 }
  
  person:
  { name: 'John', age: 30 }

• newPerson:
  { name: 'Mehul', age: 30 }
  
  person:
  { name: 'John', age: 30 }

• newPerson:
  { name: 'Mehul', age: 30 }
  
  person:
  { name: 'Mehul', age: 30 }

• newPerson:
  { name: 'John', age: 30 }
  
  person:
  { name: 'Mehul', age: 30 }