jQuery - resetting a variable

Question

I have a variable in a web page that gets set to a value and is of type string. When a button is clicked, it calls a function & at the end of the function, I would want to clean up anything that had been set previously. I have tried using:

$.removeData(myVar);

but it doesn't do anything. Log statements before & after that statement show that it still has the value & type both before & after the above statement.

Another unused variable has a value of undefined and a type of undefined. Both these variables happen to be global variables in the page.

How do you reset myVar to its initial state? I know it ought to be simple, but I'm missing something. Would appreciate any help.

Answer 1

Well...several possible direct answers.

myVar = undefined;
myVar = null;
delete window.myVar;

HOWEVER, I would question the logic of having the variable be global, but only be used in certain methods. Here's how it might be better to structure (with a random pseudo-example of adding up values from ajax):

addAjaxButton.onClick(function() {
  var counter = 0;
  ajax(function(addition) {
    counter += addition;
    ajax(function(moreAdd) {
      counter += moreAdd;
      alert('Total is ' + counter);
    });
  });
});

In that case, counter doesn't need to be deleted - it will just go out of scope when all AJAX is complete.

Answer 2

Just assign a value to it. If the initial state was undefined, set it to null. You don't have to do anything fancy with jQuery to kill the value.