实体框架只插入一条记录

Question

I'm saving a record in my database by passing 3 parameters, the number parameter is passed to pick the number of records from one table to another table. However the loop written inserts only 1 record instead of the number parameter passed.

I'm using the the Take() method in Entity Framework to pick the records. It inserts only the last records in the loop

public async Task<bool> Save(string company, int number, string registrationNumber)
{
    using (var trans = _dbContext.Database.BeginTransaction())
    {
        var db = new SibaCiidDbContext();
        var dbSet = _dbContext.Set<IntermediaryAssignment>();

        // pick number of records 
        var data = await (from s in db.StickerDistributions
                          where s.Dispatched == false &&  
                                s.CompanyCode == company
                          select s).Take(number).ToListAsync();

        var intermediary = (await _repo.FindBy(s => s.RegistrationNumber  == registrationNumber && 
                                                    s.Status == EntityStatus.Active)).FirstOrDefault();

        var entity = new IntermediaryAssignment();

        foreach (var sticker in data)
        {
            entity.CompanyCode = sticker.CompanyCode;
            entity.StickerCode = sticker.StickerCode;
            entity.RegistrationNumber = intermediary.RegistrationNumber;
            entity.Status = EntityStatus.Active;
            entity.CreatedDate = DateTime.Now;
            entity.Dispatched = false;
            entity.IntermediaryType = intermediary.IntermediaryType;

            dbSet.Add(entity);
        }

        trans.Commit();

        return  await _dbContext.SaveChangesAsync() > 0;
    }
}

Answer 1

You are creating one entity, and then updating it 3 times. You need to create a new entity for each new record.

Move the new IntermediaryAssignment() inside the loop.

     foreach (var sticker in data)
     {
            var entity = new IntermediaryAssignment();


            entity.CompanyCode = sticker.CompanyCode;
            entity.StickerCode = sticker.StickerCode;
            entity.RegistrationNumber = intermediary.RegistrationNumber;
            entity.Status = EntityStatus.Active;
            entity.CreatedDate = DateTime.Now;
            entity.Dispatched = false;
            entity.IntermediaryType = intermediary.IntermediaryType;


            dbSet.Add(entity);

        }