Send array via Ajax and bind to List<string> on MVC 4

Question

AJAX:

function systemsChanged(elem)
{
    var items = [];
    for (i = 0; i < elem.length; i++)
        if (elem[i].selected) {
            items.push(elem[i].value);
        }

    var post = { ids: items };

    $.ajax({
        type: "POST",
        traditional: true,
        url: "@Url.Action("LoadApplicationConfigs", "Application")",
        content: "application/json; charset=utf-8",
        dataType: "json",
        data: JSON.stringify(post),
        success: function (d) {
            alert(d.message);
        },
        error: function (xhr, textStatus, errorThrown) {
            alert("não rolo");
        }
    });
}

C# MVC 4:

[HttpPost]
public JsonResult LoadApplicationConfigs(IList<string> ids)
{
    object data = new
    {
        message = "aha!"
    };

    return new JsonResult() { Data = data };
}

It enters the post method but ids is set to null. I also tried changing ids to string[], not successfully. The return to ajax is fine: it shows the "aha!" alert. I just cant seem to be providing the accurate format to the mvc binder. Any thoughts?

Yeah as Matt says, the method is just expecting an array of strings, to get it to accept what you ware sending you would have to create a wrapper class/struct with a property called "ids", which seems pointless. — Coding Flow
– Coding Flow, Commented Sep 11, 2014 at 14:17
@mrsimon, i'm not sure if it will make a difference but I would make your param IEnumerable<string> — Coding Flow
– Coding Flow, Commented Sep 11, 2014 at 14:19

Jim Skerritt · Accepted Answer · 2014-09-11 14:48:30Z

1

Update your ajax call to this:

$.ajax({
    type: "POST",
    traditional: true,
    url: "@Url.Action("LoadApplicationConfigs", "Application")",
    content: "application/json; charset=utf-8",
    dataType: "json",
    data: post,
    success: function(d) {
        alert(d.message);
    },
    error: function(xhr, textStatus, errorThrown) {
        alert("não rolo");
    }
});

This will work with or without the traditional option.

edited Sep 11, 2014 at 14:48

answered Sep 11, 2014 at 14:35

Jim Skerritt

4,6362 gold badges31 silver badges25 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Matheus Simon Over a year ago

It worked and Ill mark it as answer but first explain the post.ids part. How come post has an attribute called ids ? would I have to change it if I changed the parameter in the method?

Jim Skerritt Over a year ago

The object that you set for the data field has to have field names that exactly match your parameter names in your action method. Because ids is expected to be IList<string>, settings ids to the entire post object would not work, the model binder would choke on this. In your original code, your ids were being set on a field called ids on your post object, and that's the data that you wanted to send to the server.

Jim Skerritt Over a year ago

On further testing, you could also just set data equal to your post object since the field name matches your action method parameter name. Whoops :) I updated the answer to demonstrate.

Matheus Simon Over a year ago

damn! how did I not try that before. I was settled on using the JSON.stringify method. thats much better thanks man!

Collectives™ on Stack Overflow

Send array via Ajax and bind to List<string> on MVC 4

1 Answer 1

4 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related