OK、これをどのように尋ねるかはよくわかりませんが、基本的には、次のようなジェネリック リスト (Of T) にプロパティを持つことができるカスタム コレクション クラスを作成したいと考えています。
Public ReadOnly Property TotalCalories() As Decimal
Get
Dim decTotal As Decimal = 0D
For Each thisFoodDiaryItem As FoodDiaryItem In Me
Dim thisNutValue As NutritionalData = (From nd In thisFoodDiaryItem.Food.NutritionalDatas Where nd.NutritionalDefinitionID = 208).FirstOrDefault
If thisFoodDiaryItem.Food.FoodWeights.Count > 0 Then
Dim decWeight As Decimal = thisFoodDiaryItem.Food.FoodWeights(0).WeightInGrams
If Not thisNutValue Is Nothing Then
Dim decCalories As Decimal = Math.Round((thisNutValue.Value * (decWeight / 100)) * thisFoodDiaryItem.Amount)
decTotal += decCalories
End If
End If
Next
Return decTotal
End Get
End Property
Public ReadOnly Property TotalSugars() As Decimal
Get
Dim decTotal As Decimal = 0D
For Each thisFoodDiaryItem As FoodDiaryItem In Me
Dim thisNutValue As NutritionalData = (From nd In thisFoodDiaryItem.Food.NutritionalDatas Where nd.NutritionalDefinitionID = 269).FirstOrDefault
If thisFoodDiaryItem.Food.FoodWeights.Count > 0 Then
Dim decWeight As Decimal = thisFoodDiaryItem.Food.FoodWeights(0).WeightInGrams
If Not thisNutValue Is Nothing Then
Dim decCalories As Decimal = Math.Round((thisNutValue.Value * (decWeight / 100)) * thisFoodDiaryItem.Amount)
decTotal += decCalories
End If
End If
Next
Return decTotal
End Get
End Property
エンティティ フレームワーク クエリを呼び出すときに、このクラスを使用する必要があります。
Protected Sub BindFoodDiaryItems()
CurrentFoodDiaryItems = New FoodDiaryItemCollection
CurrentFoodDiaryItems = (From fdi In db.FoodDiaryItems Where fdi.PersonID = CurrentSiteUser.PersonID And fdi.EntryDate = CurrentDiaryDate).ToList
If AllMeals Is Nothing Then
AllMeals = (From m In db.Meals).ToList
End If
lvMealsA.DataSource = AllMeals
lvMealsA.DataBind()
lblTotalCalories.Text = CurrentFoodDiaryItems.TotalCalories.ToString
lblTotalSugars.Text = CurrentFoodDiaryItems.TotalSugars.ToString
lblTotalFats.Text = CurrentFoodDiaryItems.TotalFat.ToString
lblTotalProtein.Text = CurrentFoodDiaryItems.TotalProtein.ToString
lblTotalCarbs.Text = CurrentFoodDiaryItems.TotalCarbs.ToString
End Sub
私はそれが次のようになると仮定しています:
Partial Public Class FoodDiaryItemCollection
Inherits List(Of FoodDiaryItem)
Sub New()
End Sub
End Class
私が得ているエラー:
タイプ 'System.Collections.Generic.List`1[NutritionBridgeModel.FoodDiaryItem]' のオブジェクトをタイプ 'NutritionBridgeModel.FoodDiaryItemCollection' にキャストできません。
ティア