按LINQ动态查询分组

Question

我试图允许用户通过querystring参数动态更改查询。我无法让小组在vb.net工作。我想要返回每个组的ID，名称和计数。

        ' load all of the types

Dim baseQuery = db.Answers _
    .Where(Function(a) a.Question.CorrectAnswer <> a.answer) _
    .Where(Function(a) a.Question.TypeId = TypeId)

If catId <> 0 Then
    baseQuery = baseQuery _
        .Where(Function(x) x.Question.CategoryId = catId) _
        .ToList()
End If

If approachId <> 0 Then
    baseQuery = baseQuery _
        .Where(Function(x) x.ApproachId = approachId) _
        .ToList()
End If

Dim grouppedQuestionTypesincorrectTotal = baseQuery _
    .GroupBy(Function(x) x.Question.TypeId) _
    .Select(Function(x) New With {.id = x.id}) _
    .ToList()

Dim grouppedCategorieincorrectTotal = baseQuery _
    .GroupBy(Function(x) x.Question.CategoryId) _
    .ToList()

Dim grouppedApproachesincorrectTotal = baseQuery _
    .GroupBy(Function(x) x.ApproachId) _
    .ToList()

ViewBag.QuestionTypes = grouppedQuestionTypesincorrectTotal
ViewBag.Categories = grouppedCategorieincorrectTotal
ViewBag.Approaches = grouppedApproachesincorrectTotal