JavaScript Interview Questions and Answers

Ques 6. How do you create a new object in JavaScript?

• var obj = new Object(); 
• var obj = {};

Ques 7. How about 2+5+"8"?

Since 2 and 5 are integers, this is number arithmetic, since 8 is a string, it's concatenation, so 78 is the result.

Ques 8. What does "1"+2+4 evaluate to?

Since 1 is a string, everything is a string, so the result is 124.

Ques 9. How do you assign object properties?

• obj["age"] = 18
• obj.age = 18

Ques 10. What's a way to append a value to an array?

arr[arr.length] = value;