插入多个数据ASP.NET MVC时出现问题

Question

I am having trouble when inserting multiple records. When I try to insert 2 records the debugger shows the count of 2 but it only saves 1 record.

This is my code in my manager class

public void Create(IEnumerable<CollectionModel> p )
{
    collection module = new collection();
    foreach (var asa in p)
    {               
        module.AccountId = 1;
        module.Amount = asa.Amount;
        module.NameSou = asa.NameSou;
        module.Date = asa.Date;
        module.CreatedDatetime = DateTime.Now;
        module.UpdatedDatetime = DateTime.Now;

        _context.collection.Add(module);
    }
    _context.SaveChanges();
}

Answer 1

Entity Framework offers two methods to insert records into database. Add() method allows to insert a single entity. AddRange() method inserts an IEnumerable collection. You can find more information from here .

Example:

 public void Create(IEnumerable<CollectionModel> args )
 {
    var modules = args.Select(asa=> new collection{
       AccountId = 1,
       Amount = asa.Amount,
       NameSou = asa.NameSou,
       Date = asa.Date,
       CreatedDatetime = DateTime.Now,
       UpdatedDatetime = DateTime.Now
      }).ToList(); 
    _context.collection.AddRange(modules);
   _context.SaveChanges();
}

Answer 2

Small Correction in your code. You are creating one module and updating the same every time. So it will always save the list of last item in your case list of last item of p.

 public void Create(IEnumerable<CollectionModel> p )
 {
   foreach (var asa in p)
     {   
       collection module = new collection();            
       module.AccountId = 1;
       module.Amount = asa.Amount;
       module.NameSou = asa.NameSou;
       module.Date = asa.Date;
       module.CreatedDatetime = DateTime.Now;
       module.UpdatedDatetime = DateTime.Now;

      _context.collection.Add(module);
    }
   _context.SaveChanges();
 }