Jquery – MVC 3 AJAX Post, List filled with Objects, but Objects Properties are Empty

Basic usage of .ajax would look something like this:

HTML:

<form id="foo">
    <label for="bar">A bar</label>
    <input id="bar" name="bar" type="text" value="" />

    <input type="submit" value="Send" />
</form>

jQuery:

// Variable to hold request
var request;

// Bind to the submit event of our form
$("#foo").submit(function(event){

    // Prevent default posting of form - put here to work in case of errors
    event.preventDefault();

    // Abort any pending request
    if (request) {
        request.abort();
    }
    // setup some local variables
    var $form = $(this);

    // Let's select and cache all the fields
    var $inputs = $form.find("input, select, button, textarea");

    // Serialize the data in the form
    var serializedData = $form.serialize();

    // Let's disable the inputs for the duration of the Ajax request.
    // Note: we disable elements AFTER the form data has been serialized.
    // Disabled form elements will not be serialized.
    $inputs.prop("disabled", true);

    // Fire off the request to /form.php
    request = $.ajax({
        url: "/form.php",
        type: "post",
        data: serializedData
    });

    // Callback handler that will be called on success
    request.done(function (response, textStatus, jqXHR){
        // Log a message to the console
        console.log("Hooray, it worked!");
    });

    // Callback handler that will be called on failure
    request.fail(function (jqXHR, textStatus, errorThrown){
        // Log the error to the console
        console.error(
            "The following error occurred: "+
            textStatus, errorThrown
        );
    });

    // Callback handler that will be called regardless
    // if the request failed or succeeded
    request.always(function () {
        // Reenable the inputs
        $inputs.prop("disabled", false);
    });

});

Note: Since jQuery 1.8, .success(), .error() and .complete() are deprecated in favor of .done(), .fail() and .always().

Note: Remember that the above snippet has to be done after DOM ready, so you should put it inside a $(document).ready() handler (or use the $() shorthand).

Tip: You can chain the callback handlers like this: $.ajax().done().fail().always();

PHP (that is, form.php):

// You can access the values posted by jQuery.ajax
// through the global variable $_POST, like this:
$bar = isset($_POST['bar']) ? $_POST['bar'] : null;

Note: Always sanitize posted data, to prevent injections and other malicious code.

You could also use the shorthand .post in place of .ajax in the above JavaScript code:

$.post('/form.php', serializedData, function(response) {
    // Log the response to the console
    console.log("Response: "+response);
});

Note: The above JavaScript code is made to work with jQuery 1.8 and later, but it should work with previous versions down to jQuery 1.5.

You could send them as JSON request:

var categoryModel = {
    categoryID: 1,
    categoryName: "Beverage"
};
var productModel = {
    productID: 1,
    productName: "Chai"
};
$.ajax({
    url: '@Url.Action("ModelTwo")',
    type: 'post',
    dataType: 'json',
    // It is important to set the content type
    // request header to application/json because
    // that's how the client will send the request
    contentType: 'application/json',
    data: JSON.stringify({ cat: categoryModel, prd: productModel }),
    cache: false,
    success: function (result) {
        alert(result);
    },
    error: function (xhr, ajaxOptions, thrownError) {
        alert(thrownError);
    }
});

The JSON.stringify method that I am using in my example is natively built-in all modern browsers but if you need to support legacy browsers you could include the json2.js script to your page.

This should correctly bind to the following action:

[HttpPost]
public ActionResult ModelTwo(Category cat, Product prd)
{
    return Json(new { message = "this took multiple model..." });
}

But I would recommend you defining a view model:

public class MyViewModel
{
    public Category Cat { get; set; }
    public Product Prd { get; set; }
}

and then have your controller action take this view model:

[HttpPost]
public ActionResult ModelTwo(MyViewModel model)
{
    return Json(new { message = "this took a single view model containing multiple models ..." });
}

and of course the client side code stays the same.