How can I get form data with JavaScript/jQuery?

Question

Is there a simple, one-line way to get the data of a form as it would be if it was to be submitted in the classic HTML-only way?

For example:

Answer 1

showing form input element fields and input file to submit your form without page refresh and grab all values with file include in it here it is

on Submit button page will send ajax request to your php file.

$('#imageUploadForm').on('submit',(function(e) 
{
     fname = $('#fname').val();
     lname =  $('#lname').val();
     address =  $('#address').val();
     phoneno =  $('#phoneno').val();
     file =  $('#file').val();
     e.preventDefault();
     var formData = new FormData(this);
     formData.append('file', $('#file')[0]);
     formData.append('fname',$('#fname').val());
     formData.append('lname',$('#lname').val());
     formData.append('phoneno',$('#phoneno').val());
     formData.append('address',$('#address').val());
     $.ajax({
		type:'POST',
                url: "test.php",
                //url: '',

                data:formData,
                cache:false,
                contentType: false,
                processData: false,
                success:function(data)
                {
                     alert('Data with file are submitted !');

                }

     });

}))