linq to entities can not convert int to string

Question

I try to filtering the data that return to kendo combo box, the filtering is based on the ID, I need to return all records that contains the filtration text not only the equals one, so what I did is to cast the ID to string as the following snip

Items = Mapper.Map<List<PurchaseOrder>, List<PurchaseOrderViewModel>>(
                purchaseOrderRepository.GetMany(x => 
                                                x.PurchaseOrderID
                                                 .ToString()
                                                 .Contains(text))
                                                 .ToList());

but it's always return linq to entities does not recognize the method 'system.string tostring()'

so I tried to convert the dbset to list before the where statement as I found in another post LINQ to Entities does not recognize the method 'System.String ToString()' method in MVC 4 but I got another error says that the list does not contains a definition for Where (dbSet is an instance of IDbSet)

public virtual IList<T> GetMany(Expression<Func<T, bool>> where)
{

    return dbset.ToList().Where(where).ToList();
}

here is My original(current) get method

sing System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.Entity;
using System.Data;
using System.Linq.Expressions;
using Spine.ERP.DataAccess.DbFirstDataAccess;
using Spine.ERP.DataModel.Helpers;
namespace Spine.ERP.DataAccess.Infrastructure
{
    public abstract class RepositoryBase<T> where T : class
    {

        private SSSDBEntities dataContext;

        private readonly IDbSet<T> dbset;

        protected RepositoryBase(IDatabaseFactory databaseFactory)
        {
            DatabaseFactory = databaseFactory;
            dbset = DataContext.Set<T>();
        }

       protected IDatabaseFactory DatabaseFactory
        {
            get;
            private set;
        }


        protected SSSDBEntities DataContext
        {
            get { return dataContext ?? (dataContext = DatabaseFactory.Get()); }
        }
    public virtual IQueryable<T> GetMany(Expression<Func<T, bool>> where)
        {
            return dbset.Where(where);
        }
  }
}

Any other thing can I do to solve this problem?

Michael Mairegger · Accepted Answer · 2013-11-12 09:21:41Z

10

There is a SqlFunctions class available that contains many SQL-functions that may be used for LINQ. Try a look at SqlFunctions.StringConvert

Items = Mapper.Map<List<PurchaseOrder>, List<PurchaseOrderViewModel>>(
                purchaseOrderRepository
                   .GetMany(x => SqlFunctions
                                  .StringConvert((double?) x.PurchaseOrderID)
                                  .Contains(text))
                                  .ToList());

Unfortunately there is only a SqlFunctions.StringConvert(double? number) and no SqlFunctions.StringConvert(int? number). But I always convert the integer number to a double and it works as expected.

Edit: You are calling ToList prior Where. Therefore that SqlFunctions can only be called in a LINQ to Entity query any SqlFunctions after a ToList() is illegal.

Try without your GetMany Method:

purchaseOrderRepository.Set<PurchaseOrder>()
   .Where(x => SqlFunctions
       .StringConvert((double?) x.PurchaseOrderID)
       .Contains(text))

edited Nov 12, 2013 at 9:21

answered Nov 11, 2013 at 9:27

Michael Mairegger

7,35133 silver badges44 bronze badges

Sign up to request clarification or add additional context in comments.

26 Comments

Wael Joulani Over a year ago

Thanks for your reply but I try this solution before but the same error return

Michael Mairegger Over a year ago

Stange, it should work. I have never had a problem with that. I cannot see the reason why with this code the same error should arise. Are you somewhere calling ToString()

Wael Joulani Over a year ago

No I didn't call ToString() anywhere

Michael Mairegger Over a year ago

I cannot understand why you get exactly the same error. At least it should be different. (I have edited the above code: not the cast ist to double? instead of double; maybe thats the problem)

Wael Joulani Over a year ago

Thank for your help, but it's still raise the same error maybe it should convert to List first then filtering, but I can not do that because it's always return that the where not found

|

Collectives™ on Stack Overflow

linq to entities can not convert int to string

1 Answer 1

26 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

26 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related