Internet Explorer: “console is not defined” Error

Question

I was using console.log() in some JavaScript I wrote and an error of: console is not defined was thrown in Internet Explorer (worked fine in other

Answer 1

If console itself doesn't exist at all, it throws an error because you're accessing an undefined variable. Just like if(abc) {} throws an error.

Since console resides in window, and window does always exist, this should work:

if(window.console) ...

Basically, accessing an property that doesn't exist is free and doesn't throw an error (it just evaluates to undefined, failing the if condition). However, it is illegal to access an undeclared variable.