C#-> ADO.NET和LINQ [英] C# -> ADO.NET and LINQ

问题描述

我创建到表Orders(Northwind数据库)的tuped数据集
我需要:
选择一个以上订单的区域
而且我有一个查询问题，因为此表中的ShipRegion列中有许多NULL ...
下一个代码是错误的，我该如何选择ShipRegion不为NULL的行??????

I create tuped dataset to table Orders (Northwind database)
and i need:
select regions where it is more than one order
and i have a problem with query, becouse in this table many NULLs in column ShipRegion...
next code is wrong, how i can select rows where ShipRegion is not NULL ??????

var Query = from t in ordersDataTable.Orders
                       where t.ShipRegion != null
                       select t;//new { OrderID = t.OrderID, City = t.ShipCity, Region = t.ShipRegion, Country = t.ShipCountry };
           dataGridView2.DataSource = Query.AsDataView();

这是错误.....但是我如何选择ShipRegion不为NULL的行????

it is error.....but how i can select rows where ShipRegion is not NULL ??????

推荐答案

var Query = from t in ordersDataTable.Orders
                       where t.ItemArray.Any(r => r != null && r != DBNull.Value)
                       select t;//new { OrderID = t.OrderID, City = t.ShipCity, Region = t.ShipRegion, Country = t.ShipCountry };

但是我只需要在ShipRegion

But I need this only to column ShipRegion

var Query = from t in ordersDataTable.Orders
                       where t.Field<string>("ShipRegion") != null
                       select t;//new { OrderID = t.OrderID, City = t.ShipCity, Region = t.ShipRegion, Country = t.ShipCountry };</string>

YEAAAAAH)

YEAAAAAH )

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