Strictly judge NaN in JavaScript, while javascript judges nan

Strictly judge NaN in JavaScript, while javascript judges nan

I also encountered this question on FreeCodeCamp:

Delete all values in the array.

In JavaScript, the false values include false, null, 0, "", undefined, and NaN.

For NaN judgment, JS provides the function isNaN (). However, the isNaN () function can only determine whether the variable is not a number, but not whether the variable value is NaN.

Therefore, the nature of the application NaN:

> NaN = NaN; false // always return false

We can use = to determine whether the variable is NaN. You only need to determine whether the variable is equal to itself. In case of inequality, the value of the variable is NaN.

Summary

The above section describes how to strictly judge NaN in JavaScript. I hope it will be helpful to you. If you have any questions, please leave a message. The editor will reply to you in time!