如何迭代linq-to-sql查询结果的结果并附加结果？

Question

我是C#和Linq-to-Sql的新手.

我有一个这种形式的表'InstrumentTypes':

typeId(int)  | type(varchar)  |  subttype(varchar)

101               Keys           keyboard
102               Keys           accessories
103               Guitar         acoustic
104               Guitar         electric

我需要根据'type'搜索作为输入从表中获取所有'typeId',并且所有typeId都需要绑定到ASP Repeater.

到目前为止,我已经编写了以下代码:

// requestType contains the type from the search
var type = (from m in database.InstrumentTypes
            where m.type == requestType
            select m);
foreach(var typeId in type)
{
    //code
}

我无法弄清楚如何迭代查询结果,将它们存储在数据结构中并将它们绑定到Repeater.

以下代码将其绑定到Repeater:

Repeater1.DataSource= //name of data structure used to store the types goes here
Repeater1.DataBind();

有人可以帮帮我吗？

编辑:对于获得的每个typeID,我想访问另一个表'Instruments'并检索属于该typeId的所有Instruments.表'仪器'是这样的:

instrumentId     typeID    name     description
1000             101       yamaha   xyz

根据Arialdo的回答,我这样做:

var type = (from m in database.InstrumentTypes
                          where m.type == requestType
                          select m);
            var instruments = new List<Instrument>();
            foreach (var i in type)
            {
                instruments.Add(from x in database.Instruments
                                where x.typeId == i.typeId
                                select x);
            }
            Repeater1.DataSource = instruments;
            Repeater1.DataBind();

但是我得到一个编译错误,说"列表中最好的重载方法匹配有一些无效的参数".我哪里错了？

Answer 1

你得到了什么

var type = (from m in database.InstrumentTypes
        where m.type == requestType
        select m);

是一个集合InstrumentTypes,而不是一组ID.

这适合我

var types = (from m in database.InstrumentTypes
        where m.type == requestType
        select m);
var ids = new List<int>();
foreach (var type in types)
{
    ids.Add(type.Id);
}

您可以轻松转换为

var ids = (from m in database.InstrumentTypes
        where m.type == requestType
        select m.Id).ToList();

[编辑]

只要您定义了InstrumentType和之间的关系,您就可以直接查询仪器并导航到相关对象Instrument.

var instruments = (from i in database.Instrument
                      where i.InstrumentType.type == requestType
                      select i);

无需单独的foreaches或查询.在i.InstrumentType将转换为join,因为你可以用SQL事件探查器验证