ASP.Net Razor Entity Framework Null Reference Exception 使用 Ajax 时

Question

I am using ASP.NET MVC 5 + Entity Framework + Oracle Databace 11g.

I am get NullReferenceException , when trying to use foreach .

@if (Model != null && Model.P_DCOBJ != null)
{
    foreach (var dcobj in Model.P_DCOBJ.Where(p => p != null)) //NRE Here
    ...
}

P_DCOBJ object of type ICollection (One to Many reference)

However, this code works fine if I just refreshes the page, the error occurs when I try to add a new account using Ajax, a record is entered into the database, but when I try to display PartialView I get an exception.

The error occurs in any attempt to access the object P_DCOBJ such as .Count.

Answer 1

I found a solution to this problem. The error occurs in another place, but for whatever reason, the debugger shows it in foreach, and did not go in this cycle, although the problem object has been located below the cycle. The facility was related entity relationship existed, but the object is equal to Null.

SOLUTION:

If you experience this problem, check all the objects on the current page, or PartialView is equal to NULL .