JQuery sortable draggable bug.

JQuery sortable Update event calls twice when you bind it to class, not to id and when you drag item to other connectable block.

Jquery

$(".MyClass1, .MyClass2").sortable({
    connectWith: ".connectedSortable",
    update: function (event, ui) {
                alert("twice!");
            }})

Very simple solution is to change event "update" to "stop":

Jquery

$(".MyClass1, .MyClass2").sortable({

    connectWith: ".connectedSortable",

    stop: function (event, ui) {

                alert("once!");

            }})

Entity Framework. "New transaction is not allowed because there are other threads running in the session."

Task: Resolve error.
Solution: Use new context to update item in iteration.

Explanation:
This exception occurs in the following code:

C#

MyContext db=new MyContext();
var ListOfEntities=from p in db.Entity select p;
foreach(var item in ListOfEntities)
{
    item.Text="Changed!";
    db.SaveChanges();
}

In the following example it will be OK:

C#

MyContext db=new MyContext();

var ListOfEntities=from p in db.Entity select p;

foreach(var item in ListOfEntities)

{

    MyContext anotherDB =new MyContext();

    var MyItem=(from p in anotherDB where p.ID=item.ID select p).FirstOrDefault();

    MyItem.Text="Changed!";

    anotherDB.SaveChanges();

}

ASP.NET MVC 3 bug (Html helpers)

If your model has ID parameter then Html helper will replace it with ID from QueryString.
It will take from here ==> "/MyControler/someaction/ID"
not from here ==> "model=>model.ID"

Solution: Write your html inputs yourself if you have ID parameter in Model.