JS int array to MVC3 controller

For MVC3 you need to configure jQuery to use traditional, "shallow" serialisation.. See here.

Client-side AJAX request:

jQuery.ajaxSettings.traditional = true; //enable "shallow" serialisation globally
$.get("someUrl", {ids : id_array });

Action Method:

public ActionResult MyAction(string[] ids) { ... }

You can do this in two different ways

1. Use $.ajax to post data to your action

$.ajax({
    url: '/myController/myAction',
    dataType: 'json',
    type: 'POST',
    contentType: 'application/json; charset=utf-8',
    traditional: true,
    data: $.toJSON(json),
    success: function (data, textStatus, jqXHR) {
    ...
    }
});

Your action should look like this one

public class myController
{
    [HttpPost]
    public ActionResult myAction(List<int> json)
    {
        ....
    }
}

2. Use $.post to post your data

$.post(
    '/myController/myAction',
    { json: $.toJSON(products) },
    function (data) {
    ...
});

In your action you should deserialize JSON string

public class myController
    {
    public ActionResult myAction(string json)
    {
        JavaScriptSerializer serializer = new JavaScriptSerializer();
        List<int> list = serializer.Deserialize<List<int>>(json);
    }
}

You need to download and include jquery.json-2.2.min.js to your code.

http://code.google.com/p/jquery-json/downloads/detail?name=jquery.json-2.2.min.js

You need to use

$.ajax({
    url: someUrl, 
    data: id_array.map( function(item){ return {name:'ids',value:item}; })
})

That is because in order to receive a list on the backend, the data need to be send in the form ids=3&ids=5&ids=1&ids=7

For IE versions that do not support .map use

function arrayToParamObject(name,array){
    var obj = [];
    for (var i = 0, len = array.length; i< len; i++){
        obj.push( {name: name, value: array[i] } );
    }
    return obj;
}

and use it

$.ajax({
    url: someUrl, 
    data: arrayToParamObject('ids', id_array)
})