How to get the ID of the list item just inserted using SP.UI.ModalDialog.showModalDialog

Question

If I am using JavaScript Client Object Model and SP.UI.ModalDialog.showModalDialog to display a form to enter a new list item, how can I get the ID of that item after its been added?

Example javascript

var options = {};
options.url = "/YOUR_SITE/Lists/YOUR_LIST/NewForm.aspx";
options.dialogReturnValueCallback =
           function (dialogResult, returnValue)
              {
                  console.log("dialogResult=" + dialogResult +
                              " returnValue=" + returnValue);
                  // dialogResult will be 1 if saved hit, 0 otherwise
                  // returnValue will be undefined
              }
SP.UI.ModalDialog.showModalDialog(options);

Answer 1

I think you will have to write a CAML query youself and retrieve it. Or use SPGetLastItemId method of SPServices library to get it.

Answer 2

This might be worth a try.

Insert the list item using the SPListItem.Add() method?

This method, creates an item but requires the SPListItem.Update method to actually add the item to the list. In between, I suppose you would be able to get the Id of the list item.

Your code block would look something similar to this -

     using (SPSite site = new SPSite("http://localhost"))
        {
            using (SPWeb web = site.OpenWeb())
            {
                SPList list = web.GetList("/lists/announcements");
                SPListItemCollection items = list.Items;

                SPListItem item = items.Add();
                \\Retrieve the Id from the item object and do the manipulations required.
                item.Update();
             }
         }