1 using (var trans = _db.Database.BeginTransaction()) //EF 6.0版本；EF 4.0版本是：_db.Database.Connection.BeginTransaction()
 2 {
 3 
 4 //业务逻辑代码
 5 
 6 _db.Entry<Model>(model).State = System.Data.Entity.EntityState.Add;
 7 }
 8 }
 9 try
10 {
11 _db.SaveChanges();
12 trans.Commit();
13 }
14 catch (Exception)
15 {
16 trans.Rollback();
17 }
18 }