Save list to database entity framework

Question

I have the following code:

 internal static bool SaveUOSChangeLog(List<Contracts.DataContracts.UOSChangeLog> values, string user)
    {
        try
        {
            using(var ctx = new StradaDataReviewContext2())
            {
                values.ForEach(u => { u.Username = user; u.Changed = DateTime.Now; });
                var test = ctx.UOSChangeLog.Add(values);
                ctx.SaveChanges();
                return true;
            }
        }

The thing I want to do Is to save values to the database. However, I get a the following error message:

Here is my Contracts.DataContracts.UOSChangeLog:

   public int? Id { get; set; }
        public int Accident_nr { get; set; }
        public int Refnr { get; set; }
        public int Action { get; set; }
        public string Old_data { get; set; }
        public string New_data { get; set; }
        public DateTime SearchedFromDate { get; set; }
        public DateTime SearchedToDate { get; set; }
        public DateTime Changed { get; set; }
        public string Username { get; set; }
        public string Comment { get; set; }

And here Is my Services.StradaDataReview2Model.UOSChangeLog that are used as a DbSet

[Table("UOSChangeLog")]
    public partial class UOSChangeLog
    {
        [Required]
        public int? Id { get; set; }

        public int Accident_nr { get; set; }
        [Required]
        public int Refnr { get; set; }
        [Required]
        public int Action { get; set; }
        [Required]
        public string Old_data { get; set; }
        [Required]
        public string New_data { get; set; }
        [Required]
        public DateTime SearchedFromDate { get; set; }
        [Required]
        public DateTime SearchedToDate { get; set; }
        [Required]
        public DateTime Changed { get; set; }
        [Required]
        public string Username { get; set; }
        [Required]
        public string Comment { get; set; }
    }

your are trying to add a new List of specified class (values is a List) rather than a specific instance — apomene, Mar 17 '16 at 13:37

Alexander Derck · Accepted Answer · 2016-03-17T13:43:26.273

7

You're trying to add a list with the Add method which takes a single object, just keep it simple and use a foreach:

using(var ctx = new StradaDataReviewContext2())
{
   foreach(var value in values)
   {
       value.Username = user;
       value.Changed = DateTime.Now;
       ctx.UOSChangeLog.Add(value);
   }
   ctx.SaveChanges();
   return true;
}

Just use a simple foreach, linq is a querying language, not a modifying language.

edited Mar 17 '16 at 13:43

answered Mar 17 '16 at 13:40

Alexander Derck

13,818
5
54
76

@Bryan That's the best option, by using linq foreach you're not actually gaining anything – Alexander Derck Mar 17 '16 at 13:50
Hi again, I still get the same error when doing like you do. – Bryan Mar 17 '16 at 14:46
@Bryan `value` is of type `UOSChangeLog` right? Can you copy the error message? – Alexander Derck Mar 17 '16 at 14:48
Here u can find a printscreen on the values of value list: http://postimg.org/image/56uxs9yzb/ and here you can find the error message: http://postimg.org/image/4felk4dir/ – Bryan Mar 17 '16 at 15:00
1

@Bryan They're of different types. Your values are from `Contracts.DataContracts` namespace, and your objectcontext is `Strada.DataReview...` namespace. You'll have to create the right object to add it (of the `Strada` namespace). – Alexander Derck Mar 17 '16 at 15:04
U mean that I must use the Model for my DbSet? – Bryan Mar 17 '16 at 15:10
@Bryan Yes, create a new model of your DbSet and fill in the properties from the other object. You can't add an object of another type to the dbset – Alexander Derck Mar 17 '16 at 15:13
AlexanderDerck: Thank u :) – Bryan Mar 17 '16 at 15:13

score 7 · Answer 2 · answered Aug 22 '17 at 14:50

7

Please use addrange method.

db.TheTable.AddRange(TheList)
db.SaveChanges();

answered Aug 22 '17 at 14:50

Ellix4u

566
5
9

score 4 · Answer 3 · answered Mar 17 '16 at 13:43

4

You can use Entity Framework's .AddRange method to add a collection of objects to your Db.

MSDN

It will look like:

       using(var ctx = new StradaDataReviewContext2())
        {
            values.ForEach(u => { u.Username = user; u.Changed = DateTime.Now; });
            var test = ctx.UOSChangeLog.AddRange(values);
            ctx.SaveChanges();
            return true;
        }

answered Mar 17 '16 at 13:43

Dan Orlovsky

1,045
7
18

1

List implements IEnumerable MSDN - https://msdn.microsoft.com/en-us/library/6sh2ey19(v=vs.110).aspx -- Stack Overflow - http://stackoverflow.com/questions/4700613/convert-from-list-into-ienumerable-format – Dan Orlovsky Mar 17 '16 at 14:38
Ah okey. But I Still get same error described In my question. – Bryan Mar 17 '16 at 14:49
Stupid question: your context does inherit DbContext, correct? – Dan Orlovsky Mar 17 '16 at 15:04
@DanOrlovsky If I call List.Clear() after AddRange, will the db still have the data? – Austin_Anderson Oct 20 '17 at 15:20
@Austin_Anderson - so long as you savechanges, you should be OK. – Dan Orlovsky Oct 20 '17 at 15:36

Save list to database entity framework

3 Answers3