Post JavaScript array with AJAX to asp.net MVC controller

Question

My controller:

[HttpPost]
public ActionResult AddUsers(int projectId, int[] useraccountIds)
{
    ...
}

I'd like to post the parameters to the controller via AJAX. Passing the int projectId isn't a problem, but I can't manage to post the int[].

My JavaScript code:

function sendForm(projectId, target) {
    $.ajax({
        traditional: true,
        url: target,
        type: "POST",
        data: { projectId: projectId, useraccountIds: new Array(1, 2, 3) },
        success: ajaxOnSuccess,
        error: function (jqXHR, exception) {
            alert('Error message.');
        }
    });
}

I tried it with a test array but no success. :( I also tried to set traditional: true, or contentType: 'application/json; charset=utf-8' but no success as well ...

The int[] useraccountIds posted to my controller is always null.

Answer 1

You could define a view model:

public class AddUserViewModel
{
    public int ProjectId { get; set; }
    public int[] userAccountIds { get; set; }
}

then adapt your controller action to take this view model as parameter:

[HttpPost]
public ActionResult AddUsers(AddUserViewModel model)
{
    ...
}

and finally invoke it:

function sendForm(projectId, target) {
    $.ajax({
        url: target,
        type: 'POST',
        contentType: 'application/json',
        data: JSON.stringify({ 
            projectId: projectId, 
            userAccountIds: [1, 2, 3] 
        }),
        success: ajaxOnSuccess,
        error: function (jqXHR, exception) {
            alert('Error message.');
        }
    });
}