Send FormData and String Data Together Through JQuery AJAX?

var fd = new FormData();
var file_data = $('input[type="file"]')[0].files; // for multiple files
for(var i = 0;i<file_data.length;i++){
    fd.append("file_"+i, file_data[i]);
}
var other_data = $('form').serializeArray();
$.each(other_data,function(key,input){
    fd.append(input.name,input.value);
});
$.ajax({
    url: 'test.php',
    data: fd,
    contentType: false,
    processData: false,
    type: 'POST',
    success: function(data){
        console.log(data);
    }
});

Added a for loop and changed .serialize() to .serializeArray() for object reference in a .each() to append to the FormData.

I always use this.It send form data using ajax

$(document).on("submit", "form", function(event)
{
    event.preventDefault();

    var url=$(this).attr("action");
    $.ajax({
        url: url,
        type: 'POST',            
        data: new FormData(this),
        processData: false,
        contentType: false,
        success: function (data, status)
        {

        }
    });
});

well, as an easier alternative and shorter, you could do this too!!

var fd = new FormData();

var file_data = object.get(0).files[i];
var other_data = $('form').serialize(); //page_id=&category_id=15&method=upload&required%5Bcategory_id%5D=Category+ID

fd.append("file", file_data);

$.ajax({
    url: 'add.php?'+ other_data,  //<== just add it to the end of url ***
    data: fd,
    contentType: false,
    processData: false,
    type: 'POST',
    success: function(data){
        alert(data);
    }
});