.net - 从列表中过滤或删除(T 个)

Question

我有一个方法，它接受对象列表。
在保留对象之前，我必须在某些给定条件下删除其中一些对象

例如(不是理想的!):

A Company can have an Id and a list of Branches and a IsDeleted flag.
A Branch can have an Id and a list of Managers and a IsDeleted flag
A Manager can have an Id and a IsDeleted flag
Company -->Branches-->Managers

忽略 Id = 0 和 IsDeleted = True 的组合的简单或最佳过滤方法是什么，以便我可以迭代它并执行具体操作 - 请参阅下面的函数

• 如果公司被标记为 Id = 0 且 IsDeleted 那么我想完全忽略它
• 但如果只有分支被标记为 Id=0 并被删除，那么公司应该没有分支
• 如果只有经理被标记为 Id=0 且已删除，则公司和分公司应该在那里

Private Function(comp as List(Of Company)) as Boolean
    'filter comp here and pass it to for loop??
    Dim filteredList as ...
    For each c as Company in filteredList 
    'do company specifis here
        For each b as Branch in c.Branches
        'do branch specific here
            For Each m as Manager in b.Managers
            'do manager specific here
            Next
        Next
    Save(c) ' saves child objects as well    
    Next
End Function

Answer 1

您可以使用 Linq:

Dim filtered = From c In comp Where Not c.IsDeleted OrElse c.Id <> 0
             From b In c.Branches Where Not b.IsDeleted OrElse b.Id <> 0
             From m In b.Managers Where Not m.IsDeleted OrElse m.Id <> 0
             Select New With {.Company = c, .Branch = b, .Manager = m}

For Each x In filtered
    Dim c As Company = x.Company
    Dim b As Branch = x.Branch
    Dim m As Manager = x.Manager
Next

或者，如果您想单独枚举每种类型:

Dim filteredComp = From c In comp Where Not c.IsDeleted OrElse c.Id <> 0
Dim filteredBranch = From c In filteredComp
                   From b In c.Branches Where Not b.IsDeleted OrElse b.Id <> 0
                   Select b
Dim filteredManager = From b In filteredBranch
                   From m In b.Managers Where Not m.IsDeleted OrElse m.Id <> 0
                   Select m

For Each c In filteredComp

Next
For Each b In filteredBranch

Next
For Each m In filteredManager

Next