try something like following.
foreach (var child in modifiedParent.ChildItems)
{
context.Childs.Attach(child);
context.Entry(child).State = EntityState.Modified;
}
context.SaveChanges();
See the following link.
문제
I am getting this error after click Save (update) my form:
The relationship could not be changed because one or more of the foreign-key properties is non-nullable. When a change is made to a relationship, the related foreign-key property is set to a null value. If the foreign-key does not support null values, a new relationship must be defined, the foreign-key property must be assigned another non-null value, or the unrelated object must be deleted.
Here is my controller (case "Save" in swich couse problem):
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Edit(UserModel userModel, string act = null, int idx = 0)
{
using (var dbContext = new userDbEntities())
{
if (userModel.User == null)
{
userModel.User = new UsersTable();
}
var newUser = userModel.User.userID == 0;
userModel.CustomTypes = dbContext.CustomTypes.ToList();
switch (act)
{
case "addcustom":
userModel.User.CustomerTables.Add(new CustomerTable
{
CustomType = new CustomType(),
UsersTable = userModel.User
});
break;
case "deletecustom":
userModel.User.CustomerTables.RemoveAt(idx);
break;
case "save":
foreach (var customer in userModel.User.CustomerTables)
{
customer.CustomType = dbContext.CustomTypes.Find(customer.CustomType.Id_NewCustomerType);
}
var dbUser = dbContext.UsersTables.Find(userModel.User.userID);
dbUser.TimeZoneId = userModel.User.TimeZoneId;
foreach (var custom in userModel.User.CustomerTables)
{
if (custom.CustomerID == 0)
dbUser.CustomerTables.Add(custom);
}
foreach (var custom in dbUser.CustomerTables.ToList())
{
var modelCustom =
userModel.User.CustomerTables.FirstOrDefault(o => o.CustomerID == custom.CustomerID);
if (modelCustom != null) //update it
{
custom.CustomType =
dbContext.CustomTypes.Find(modelCustom.CustomType.Id_NewCustomerType);
}
if (userModel.User.CustomerTables.All(o => o.CustomerID != custom.CustomerID))
dbUser.CustomerTables.Remove(custom);
}
dbContext.SaveChanges();
break;
} // end switch statements
return View("Edit", userModel);
}
}
Any idea what is wrong...
해결책
try something like following.
foreach (var child in modifiedParent.ChildItems)
{
context.Childs.Attach(child);
context.Entry(child).State = EntityState.Modified;
}
context.SaveChanges();
See the following link.
다른 팁
There is an easier way to solve this problem.
Actually this is because you have one to many relationship. When you want to delete 1 Side, you have two scenarios; You can choose cascade delete, or you can choose none.
If you select first option it will delete all the many side entities when you delete the 1 side.
You can set this option in the Entity Diagram. You Only got to select the relationship and set "End1 OnDelete" property to Cascade.
I was experiencing this message, it turned out that I was marking the object as Modified after I had removed it from it's collection instead of deleting it.
For example you don't want to call
context.Entry(child).State = EntityState.Modified;
if in fact you are trying to delete the child.
instead, as well as removing the child from the collection try something like context.DeleteObject(child)
I experienced this problem, it's complicated to explain (so please forgive the analogy), the good news is that the solution is very simple.
Assume I have a record with a one to many relationship, which also has a relationship. (A "Car" has a number of "People"; "People" have a number of "Children"). The error occurrs when removing people from car. Doing a db.Cars.Remove(person);
. Caused an unrelated error. To resolve that issue I did a db.Cars.Persons.RemoveRange(children);
<--- After this I experienced the error as stated in this question. To resolve this remove the child's children from the database (not the "Parent" but the database iteself) db.Children.RemoveRange(childrenOfPeople);
.
This is the cleanest solution to the problem using entity framework correctly without setting the state of records. Hope that helps someone.