How to unset a JavaScript variable?

Question

I have a global variable in JavaScript (actually a window property, but I don\'t think it matters) which was already populated by a previous script but I don\'t

Answer 1

You cannot delete a variable if you declared it (with var x;) at the time of first use. However, if your variable x first appeared in the script without a declaration, then you can use the delete operator (delete x;) and your variable will be deleted, very similar to deleting an element of an array or deleting a property of an object.