SQLServer查詢到C#Linq

我目前正在艱難地將我的 SQL 查詢轉換為 LINQ，以用于我正在使用 WPF 和物體框架的學校專案

這是我的 SQL 查詢（完全按照我的預期作業）

select IngrediantName,sum(IngrediantQuantity) as Quantity, IngrediantMeasurementUnit from Users
join Shopping_List
on Users.UserID = Shopping_List.ShoppingListID
join List_Item
on List_Item.ShoppingListID = Shopping_List.ShoppingListID
join Ingrediant
on Ingrediant.IngrediantID = List_Item.IngrediantID
where Users.UserID = 1
group by IngrediantName,IngrediantMeasurementUnit

這是我到目前為止的查詢

var query = from user in dbContext.Users
                        join shoppingList in dbContext.ShoppingLists on user.UserId equals shoppingList.UserId
                        join listItem in dbContext.ListItems on shoppingList.ShoppingListId equals listItem.ShoppingListId
                        join ingrediant in dbContext.Ingrediants on listItem.IngrediantId equals ingrediant.IngrediantId
                        where currentUserNumber == user.UserId
                        
                        select new
                        {
                            name = ingrediant.IngrediantName,
                            quantity = ingrediant.IngrediantQuantity,
                            unit = ingrediant.IngrediantMeasurementUnit,
                        };

這是我到目前為止所嘗試的

            var query = from user in dbContext.Users
                        join shoppingList in dbContext.ShoppingLists on user.UserId equals shoppingList.UserId
                        join listItem in dbContext.ListItems on shoppingList.ShoppingListId equals listItem.ShoppingListId
                        join ingrediant in dbContext.Ingrediants on listItem.IngrediantId equals ingrediant.IngrediantId
                        where currentUserNumber == user.UserId
                        group ingrediant by ingrediant.IngrediantQuantity into x
                        
                        select new
                        {
                            name = x.GroupBy(x => x.IngrediantName),
                            quantity = x.Sum(x => x.IngrediantQuantity),
                            unit = x.GroupBy(x => x.IngrediantMeasurementUnit),
                        };

這個回傳以下錯誤并沒有說明什么

引數型別 'System.Linq.IQueryable 1[System.Linq.IGrouping2[System.String,Microsoft.EntityFrameworkCore.Query.TransparentIdentifierFactory TransparentIdentifier 2[Microsoft.EntityFrameworkCore.Query.TransparentIdentifierFactory TransparentIdentifier2

如果有人能指出我正確的方向，我將不勝感激，如果您需要更多資訊，我一定會提供

謝謝

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更新

我在這里作業了其他人的問題的答案

var query = 
    from user in dbContext.Users
    join shoppingList in dbContext.ShoppingLists 
        on user.UserId equals shoppingList.UserId
    join listItem in dbContext.ListItems 
        on shoppingList.ShoppingListId equals listItem.ShoppingListId
    join ingrediant in dbContext.Ingrediants 
        on listItem.IngrediantId equals ingrediant.IngrediantId
    where currentUserNumber == user.UserId
    group ingrediant by new { name = ingrediant.IngrediantName, unit = ingrediant.IngrediantMeasurementUnit } into x
    select new
    {
        name = x.Key.name,
        quantity = x.Sum(x => x.IngrediantQuantity),
        unit = x.Key.unit,
    };

如果你看一下組線 group ingrediant by new { name = ingrediant.IngrediantName, unit = ingrediant.IngrediantMeasurementUnit } into x

據我了解，您使用 new 創建一個新的選擇器，然后您可以使用 x.key.name 和 x.key.unit 其中 name 和 unit 只是一些變數

標籤：C＃ sql 实体框架 林克

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