LINQ留下过滤加盟加盟

问题描述：

IEnumerable<DTOHotMealsPrice> lst = (from m in this.dbEntity.HOT_MEALS 
    join ml in this.dbEntity.HOT_MEALS_PRICE on m.MEALSID equals ml.MEALSID into mls 
    from mls1 in mls.DefaultIfEmpty() 
    where mls1.HOTID==hotelId 
    select new DTOHotMealsPrice 
    { 
     MEALSID = m.MEALSID, 
     MEALSNAME = m.MEALSNAME, 
     CHPRICE = mls1.CHPRICE, 
     PRICE = mls1.PRICE, 
     HOTID = mls1.HOTID 
    }).Distinct().ToList();

我想列出所有HOT_MEALS并与 HOT_MEALS_PRICE加入时，就可以了mealsid参考

当mls1.HOTID==hotelId，这将越来越innerjoin结果怎么可能将一个正确的结果

请提供你的表结构。 –

'public partial class HOT_MEALS { public short MEALSID {get;组; } public string MEALSNAME {get;组; } } public partial class HOT_MEALS_PRICE { public short MEALSID {get;组; } public int HOTID {get;组; } public Nullable PRICE {get;组; } public Nullable CHPRICE {get;组; ' }' –

答

双向解决方案

删除哪里案例

加入其中案例在加入表

显示在哪里案例吹LINQ查询

第一查询

IEnumerable<DTOHotMealsPrice> lst = (from m in this.dbEntity.HOT_MEALS 
join ml in this.dbEntity.HOT_MEALS_PRICE.where(c=>c.HOTID==hotelId) on m.MEALSID equals ml.MEALSID into mls 
from mls1 in mls.DefaultIfEmpty() 
select new DTOHotMealsPrice 
{ 
    MEALSID = m.MEALSID, 
    MEALSNAME = m.MEALSNAME, 
    CHPRICE = mls1.CHPRICE, 
    PRICE = mls1.PRICE, 
    HOTID = mls1.HOTID 
}).Distinct().ToList();

二是：

IEnumerable<DTOHotMealsPrice> lst = (from m in this.dbEntity.HOT_MEALS 
join ml in this.dbEntity.HOT_MEALS_PRICE on m.MEALSID equals ml.MEALSID into mls 
from mls1 in mls.where(c=>c.HOTID==hotelId).DefaultIfEmpty() 
select new DTOHotMealsPrice 
{ 
    MEALSID = m.MEALSID, 
    MEALSNAME = m.MEALSNAME, 
    CHPRICE = mls1.CHPRICE, 
    PRICE = mls1.PRICE, 
    HOTID = mls1.HOTID 
}).Distinct().ToList();

LINQ留下过滤加盟加盟

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