发布多个AJAX数据

I'm trying to POST multiple AJAX data to update.php. This is my code at the moment:

$.ajax({  
    url:"update.php",  
    method:"POST",  
    data: $('#update_form').serialize(),   
    beforeSend:function(){  
        $('#update').val("Geupdate!");  
    },  
    success:function(data){  
        $('#update_form')[0].reset();  
        $('#add_data_Modal').modal('hide');  
        $('#employee_table').html(data);  
    }  
}); 

However I also want to sent an ID within the data. This is the form that I'm using.

 <form method="post" id="update_form">
     <label>Notitie:</label>
     <input type="text" name="name" id="' . $row["id"] . '" class="form-control" value='.$row["name"].' width="100%">
     <br />
     <input type="submit" name="update" id="update" value="Opslaan" class="btn btn-success" />
 </form> 

How can I combine data: $('#update_form').serialize() and id="' . $row["id"] . '" together?

I tried a few combinations but I can't find the correct answer. Here is what I've tried:

data: $('#update_form').serialize(), id: <?php echo $row["id"] ?> 

You are serializing entire form, which includes your textbox data as well. So, you don't need to explicitly add each element of form.

The .serialize() method creates a text string in standard URL-encoded notation. It can act on a jQuery object that has selected individual form controls, such as <input>, <textarea>, and <select>: $("input, textarea, select" ).serialize();

So, whatever element added in form (<input>, <textarea>, and <select>) gets serialized implicitly. So, in case, you wanted to pass additional data along with form, then you can create a hidden field inside your form.

One simple way is add a hidden input to the form so serialize() will include the id

<form method="post" id="update_form">

   <input type="hidden" name="id" value="' . $row["id"] . '" > 

  <label>Notitie:</label>
  <input type="text" name="name" id="' . $row["id"] . '" class="form-control" value='.$row["name"].' width="100%">
  <br />
  <input type="submit" name="update" id="update" value="Opslaan" class="btn btn-success" />
</form>

I don't use jQuery so this is a bit of a "stab in the dark" but you could alternatively use a FormData object and append a new parameter & value to it like this perhaps.

$.ajax({ 
    var form=$('#update_form');
    var fd=new FormData( form[0] );
        fd.append('id', document.querySelector('input[name="name"]').id );

    url:'update.php',  
    method:'POST',  
    data: fd,  
    beforeSend:function(){  
        $('#update').val('Geupdate!');  
    },  
    success:function(data){  
        form[0].reset();  
        $('#add_data_Modal').modal('hide');  
        $('#employee_table').html(data);  
    }  
});