SQL SERVER 多数据导入

 public bool CreateTB_PROPERTY_MODELLByList(List<TB_PROPERTY_MODEL> entity)
        {
            try
            {
                if (entity.Count > 0)
                {
                    string strsql = "delete  from TB_PROPERTY_MODEL where DocumentModel=‘" + entity[0].DocumentModel + "‘";
                    _dbContext.Database.ExecuteSqlCommand(strsql);
                }
                //将集合转换成DataTable
                DataTable dtTable = Untity.ListToDataTable(entity);

                var sqlConn = (SqlConnection)_dbContext.Database.Connection; ;
                sqlConn.Open();
                using (SqlTransaction transaction = sqlConn.BeginTransaction())
                {
                    using (SqlBulkCopy bulkCopy = new SqlBulkCopy(sqlConn, SqlBulkCopyOptions.Default, transaction))
                    {
                        bulkCopy.BatchSize = 10000;
                        bulkCopy.BulkCopyTimeout = 600;
                        bulkCopy.DestinationTableName = "TB_PROPERTY_MODEL";
                        try
                        {
                            //这里列一定要和数据库中的表的列要一样.和数据类型也一样。不然无法导入
                            foreach (DataColumn col in dtTable.Columns)
                            {
                                bulkCopy.ColumnMappings.Add(col.ColumnName, col.ColumnName);
                            }
                            bulkCopy.WriteToServer(dtTable);
                            transaction.Commit();
                        }
                        catch (Exception ex)
                        {
                            transaction.Rollback();
                            LogHelper.Error(ex.Message);
                            throw ex.InnerException;
                        }
                        finally
                        {
                            bulkCopy.Close();
                            sqlConn.Close();
                        }
                    }
                }
                return true;
            }
            catch (EntityException ex)
            {
                LogHelper.Error(ex.Message);
                throw ex.InnerException;
            }
            catch (DbException ex)
            {
                LogHelper.Error(ex.Message);
                throw ex.InnerException;
            }
        }