Preventing EF4 ConstraintException when invoking TryUpdateModel
- by twk
Given following ASP.NET MVC controller code:
[HttpPost]
public ActionResult Create(FormCollection collection)
{
string[] whitelist = new []{ "CompanyName", "Address1", "Address2", ... };
Partner newPartner = new Partner();
if (TryUpdateModel(newPartner, whitelist, collection))
{
var db = new mainEntities();
db.Partners.AddObject(newPartner);
db.SaveChanges();
return RedirectToAction("Details/" + newPartner.ID);
}
else
{
return View();
}
}
The problem is with the Entity Framework 4: the example Partner entity is mapped to a database table with it's fields NOT ALLOWED to be NULL (which is ok by design - they're required).
Unfortunately, invoking TryUpdateModel when some of the properties are nulls produces ConstraintException which is not expected! I do expect that TryUpdateModel return false in this case.
It is ok that EF wouldn't allow set a property value to null if it should not be, but the TryUpdateMethod should handle that, and add the error to ModelState errors collection.
I am wrong, or somebody screwed the implementation of TryUpdateModel method?
