Question

我有一个问题，问题是我想选择该地区的所有葡萄酒，我做一些代码，但他重复该地区我总是喜欢3种葡萄酒，他向我展示了3种葡萄酒但分开了，我选择了typeWine。

LINQ的

 public List<ZoneModel> GetRegion(int typeWine)
        {
            var query = (from m in db.Wine
                join si in db.ImageWine on m.idWine equals si.idWine into f
                join r in db.Region on m.idRegion equals r.idRegion
                where m.idTypeWine == typeWine
                select new ZoneModel()
                {
                    Name = r.name,
                    Description = r.description,
                    ImageUrl = r.Image.urlImage,
                    BeveragesList = new List<BeverageModel>()
                    {
                        new BeverageModel()
                        {
                            Name = m.name,
                            ShortName = m.shortName,
                            Price = m.price,
                            Description = m.description,
                            AlcoholContent = m.alcoholContent,
                            Region = m.Region.name,
                            WineCaste = m.wineCaste,
                            UrlImageList = f.Select(i => _url + i.Image.urlImage).ToList(),

                 }}}
                ).ToList();


            return query;
        }

返回json：

[{
    "Name": "Douro",
    "ImageUrl": "douro.jpg",
    "Description": "Douro Descrição",
    "BeveragesList": [{
        "AlcoholContent": "12",
        "Region": "Douro",
        "WineCaste": "Castas",
        "DishList": null,
        "WineCategoryEnum": null,
        "WineEnum": null,
        "Id": null,
        "UrlImageList": ["http://..net/Images/vinho1.jpg", "http://..net/Images/vinho2.jpeg"],
        "Name": "Vinho Douro",
        "ShortName": "Vinho Douro",
        "Description": "Descrição Vinho",
        "Price": "12"
    }]
}, {
    "Name": "Douro",
    "ImageUrl": "douro.jpg",
    "Description": "Douro Descrição",
    "BeveragesList": [{
        "AlcoholContent": "12",
        "Region": "Douro",
        "WineCaste": "Castas",
        "DishList": null,
        "WineCategoryEnum": null,
        "WineEnum": null,
        "Id": null,
        "UrlImageList": ["http://..net/Images/vinho1.jpg"],
        "Name": "Vinho douro2",
        "ShortName": "Vinho douro2",
        "Description": "Descrição",
        "Price": "12"
    }]
}]

Answer 1

您所描述的内容听起来更像是查找：

query.ToLookup(item => item.Name, s=> s.BeveragesList);
// or if you're confident there are no duplicates
query.ToDictionary(item => item.Name, s=> s.BeveragesList);
// to flatten the list project your results using:
query.ToLookup(item => item.Name, s=> s.BeveragesList)
  .Select(s=> new { 
                      Name = s.Key, 
                      BeveragesList = s.SelectMany(t => t).ToArray()
                   })
  .ToArray()
// instead of
query.ToList(...);

Answer 2

大多数情况下无需加入：

 public List<ZoneModel> GetRegion(int typeWine)
        {
            var query = (from m in db.Wine
                join r in db.Region on m.idRegion equals r.idRegion
                where m.idTypeWine == typeWine
                select new ZoneModel()
                {
                    Name = r.name,
                    Description = r.description,
                    ImageUrl = r.Image.urlImage,
                    BeveragesList = new List<BeverageModel>()
                    {
                        new BeverageModel()
                        {
                            Name = m.name,
                            ShortName = m.shortName,
                            Price = m.price,
                            Description = m.description,
                            AlcoholContent = m.alcoholContent,
                            Region = m.Region.name,
                            WineCaste = m.wineCaste,
                            UrlImageList = m.ImageWines.Select(i => _url + i.Image.urlImage).ToList(),

                 }}}
                ).ToList();


            return query;
        }

或者拥有GroupBy

from m in db.Wine
group m.ImageWines by m.idWine into g
join r in db.Region on m.idRegion equals r.idRegion
select new { 
 ...  
 UrlImageList= g.ToList() 
 };

Linq选择区域然后列出葡萄酒

2 个答案: