How do you check for undefined and null?

Example 2: using typeof The typeof operator for undefined value returns undefined . Hence, you can check the undefined value using typeof operator. Also, null values are checked using the === operator .

Example 2: using typeof The typeof operator for undefined value returns undefined . Hence, you can check the undefined value using typeof operator. Also, null values are checked using the === operator .

But enough bragging, here’s my list of practices when dealing with null values.

But enough bragging, here’s my list of practices when dealing with null values.