how to check if a file is selected using javascript?

Question

In php this is how you would check if a file is selected:

$_FILES[\'item\'][\'size\']>0

what about in JavaScript?

I need to know

Answer 1

So lets say you have some html form and you have a custom file upload input:

Click here for uploading a new picture
 

And you want to check the filename of the file the user has chosen/selected:

Using jquery

@https://stackoverflow.com/a/5670938/2979938

For those using requireJS:

$("input:file").change(function () {
  var fileName = $(this).val();
  alert(fileName); //Do with the filename whatever you want
});