How can I distinguish 0 and empty string in javascript?

Question

Say

a="";  // empty String
b=0;

then

a==b;  // returns true

What Test could I build to return true only if I compare two empty strings or two zero's?

Answer 1

Use the strict comparison operator, ===. This will not use JavaScript's default type coercion, so you will get the correct result.

"" === 0; // false

Answer 2

use === instead of == for checking undifined and zero or false compare