How to check if input file is empty in jQuery

Brand new to JS. I am trying to check if the file input element is empty when submitting the form with jQuery/JavaScript. I have gone through a bunch of solutions and nothing is working for me. I am trying to avoid the /c/fakepath (unless there is no other option)

<input type="file" name="videoFile" id="videoUploadFile" />

This does not work:

var vidFile = $("#videoUploadFile").value;

The only way I can get the filename is if I use the following:

var vidFile = document.getElementById("videoUploadFile").files[0].name;

If there is no file available the code throws an error: >cannot read property name of undefined

which makes sense because the array is not set. but I cannot figure out how to do any error handling with this.

How do I properly grab the file input element videoUploadFile, check if it's empty, throw an error message if it's empty?

Just check the length of files property, which is a FileList object contained on the input element

if( document.getElementById("videoUploadFile").files.length == 0 ){
    console.log("no files selected");
}

Here is the jQuery version of it:

if ($('#videoUploadFile').get(0).files.length === 0) {
    console.log("No files selected.");
}

To check whether the input file is empty or not by using the file length property, index should be specified like the following:

var vidFileLength = $("#videoUploadFile")[0].files.length;
if(vidFileLength === 0){
    alert("No file selected.");
}

I know I'm late to the party but I thought I'd add what I ended up using for this - which is to simply check if the file upload input does not contain a truthy value with the not operator & JQuery like so:

if (!$('#videoUploadFile').val()) {
  alert('Please Upload File');
}

Note that if this is in a form, you may also want to wrap it with the following handler to prevent the form from submitting:

$(document).on("click", ":submit", function (e) {

  if (!$('#videoUploadFile').val()) {
  e.preventDefault();
  alert('Please Upload File');
  }

}

Questions : how to check File is empty or not?

Ans: I have slove this issue using this Jquery code

//If your file Is Empty :     
      if (jQuery('#videoUploadFile').val() == '') {
                       $('#message').html("Please Attach File");
                   }else {
                            alert('not work');
                   }

    

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="file" id="videoUploadFile">
<br>
<br>
<div id="message"></div>

  $("#customFile").change(function() { 
    var fileName = $("#customFile").val();  

    if(fileName) { // returns true if the string is not empty   
        $('.picture-selected').addClass('disable-inputs'); 
        $('#btn').removeClass('disabled');   
    } else { // no file was selected 
      $('.picture-selected').removeClass('disable-inputs'); 
      $('#btn').addClass('disabled');
    }  
  });

if (data.name == '') {
   //file doesn't exist;
}
else {
   //file exist;
}