How to check input type = "file" file or not using jquery?

Question

I have a file upload control <input id="File1" type="file" />on my page ... How do I check for an input type = "file" file or not using jquery with a click of a button upload?

Answer 1

if (jQuery('#File1').val()) { /* There are files */ }

Answer 2

Instead of jQuery, use "required". Only one attribute will check the input = file file or not. Example:

<input type="file" required/>

Answer 3

$('#upload').bind('click', function(e){
   if( $('#File1').val() != ""){
       // file selected
   }
   else{
       // no file selected
   }
});