Update tables with relations from ViewModel (EF)

Adnan Okko

8y2.9kLearn iOS Programming

I have the following entities:

BIEntities db = new BIEntities();
public class SALES
{
public int IDs {get; set;}
public string product { get; set; }
ICollection COUNTRIES { get; set; }
ICollection PRICES { get; set; }
}
public class COUNTRIES
{
public int IDc { get; set; }
public string country { get; set; }
public virtual SALES SALES { get; set; }
}
public class PRICES
{
public int IDp { get; set; }
public string price { get; set; }
public string strength { get; set; }
public virtual SALES SALES { get; set; }
}

And a ViewModel:

public class myViewModel
{
public int ID { get; set; }
public string product { get; set; }
List<string> country { get; set; }
List<string> price { get; set; }
List<string> strength { get; set; }
}

I am trying to update (edit) all entities from myViewModel:

[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Edit(int id, FormCollection collection, myViewModel myModel)
{
SALES sUpdate = db.SALES.FirstOrDefault(s => s.IDs == myModel.ID);
if (sUpdate != null)
{
db.Entry(sUpdate).CurrentValues.SetValues(myModel);
db.SaveChanges();
}
return RedirectToAction("Index");
}

I am getting this exception:

"System.InvalidOperationException: The view 'Validation failed for one or more entities. See 'EntityValidationErrors' property for more details.' or its master was not found or no view engine supports the searched locations."

Is this method correct? what other methods can I use to update the tables?

6 Replies

Know the answer? Post it — somebody with the same question will find it here.

Manav Pandya8y ago
Accepted answer
Hello

Best answer that also helped me during period of time when i was facing this issue :

https://www.c-sharpcorner.com/UploadFile/97fc7a/validation-failed-for-one-or-more-entities-mvcentity-frame/

Thanks
Adnan Okko8y ago
Actually I have been reading many articles but never found a solution for this issue.

I am trying to update COUNTRIES table like this:
var cUpdate = from c in db.COUNTRIES where c.IDc == myModel.ID select c;
COUNTRIES cc = COUNTRIES();
if (cUpdate != null)
{
   foreach (var item in cUpdate)
      {
         cc.IDc = item.IDc;
         cc.country = item.country;

      }
   db.Entry(cc).State = EntityState.Modified;
   db.SaveChanges();
}
But I get this exception:

Attaching an entity of type 'X.Models.COUNTRIES' failed because another entity of the same type already has the same primary key value. This can happen when using the Attach() method or setting the state of an entity to 'Unchanged' or 'Modified' if any entities in the graph have conflicting > key values. This may be because some entities are new and have not yet received database-generated key values. In this case use the 'Add' method or the 'Added' entity state to track the graph and then set the state of non-new entities to 'Unchanged' or 'Modified' as appropriate.
Manav Pandya8y ago
Hello

Well this is long going process which i can't explain here

So for reference you can go through below articles :

https://docs.microsoft.com/en-us/aspnet/mvc/overview/older-versions/getting-started-with-ef-5-using-mvc-4/updating-related-data-with-the-entity-framework-in-an-asp-net-mvc-application

https://docs.microsoft.com/en-us/aspnet/mvc/overview/older-versions/getting-started-with-ef-5-using-mvc-4/reading-related-data-with-the-entity-framework-in-an-asp-net-mvc-application

I hope it might help you somehow

Thanks
Adnan Okko8y ago
How can I update the other tables considering that their parameters are passed as lists; (ICollection)?
Manav Pandya8y ago
Hello

In your code you are updating only sales details , thats why only sales table is affected

Thanks
Adnan Okko8y ago
@Manav Pandya, Thanks, Now I know what caused the validation error. But I have another issue that is: only SALES table is updated. country, price and strength are passed to controller in myViewModel but are not updated after submit.