Uncaught TypeError: Cannot set property 'onmousemove' of null

Question

I'm a beginner of JS Please Help me!

How can I solve this error..?

--> Uncaught TypeError: Cannot set property 'onmousemove' of null

Answer 1

I assume you are trying to add a property to some DOM object. Now as the message says, you can not add property to variable with null as value.

Now here is the probable cause for it:
https://www.sololearn.com/post/7444/?ref=app