Question

Why does the first alert say undefined? Note that the alert is there and the textbox only appears when i dismiss the alert.

Subsequent “new” click alerts “RowId”. After i dismiss the alert, i see two boxes.

Here is my view with an Ajax.Action link which is InserterAfter.

@Ajax.ActionLink("New", "_New", new { Controller = "Test" }
    , new AjaxOptions() 
        { InsertionMode = InsertionMode.InsertAfter, UpdateTargetId = "divNew" })

<div id="divNew" />

Here is my partialview.

RowId: @Html.TextBox("RowId")<br />
<script language="javascript">
    $(document).ready(function ()
    {
        alert($('input[name="RowId"]').attr('Id'));
    });
</script>

Answer 1

Try the following in your main view:

<!-- TODO: This script should be moved to a separate javascript file
     because you should never mix markup and javascript. But for the 
     purpose of this demonstration I have left it in the view 
-->
<script type="text/javascript">
    var onSuccess = function (result) {
        $('#divNew').append(result);
    };
</script>

@Ajax.ActionLink(
    "New", 
    "_New", 
    new { controller = "Test" }, 
    new AjaxOptions() { OnSuccess = "onSuccess" }
)
<div id="divNew" />

or throw away Ajax.* helpers and use plain old jQuery:

<!-- TODO: This script should be moved to a separate javascript file
     because you should never mix markup and javascript. But for the 
     purpose of this demonstration I have left it in the view 
-->
<script type="text/javascript">
    $(function () {
        $('#mylink').click(function (result) {
            $.ajax(this.href, {
                success: function (result) {
                    $('#divNew').append(result);        
                }
            });
            return false;
        });
    });
</script>

@Html.ActionLink(
    "New", 
    "_New", 
    new { 
        controller = "Test" 
    },
    new { 
        id = "mylink" 
    }
)
<div id="divNew" />

---

This being said, if I am not mistaken and if my memory is good, I think I’ve already commented on a similar previous question of yours, but I will repeat it here so that other people can see it as well:

do not put any javascript in partial or any views whatsoever. Javascript belongs to separate files and should not be mixed with markup.

I am seeing people making this mistake over and over again and I think its important to point it out.

P.S: you probably wanted to use .attr('id') instead of .attr('Id').