主题：怎么判定上周有购买过电脑，代码要怎么写

Imports System.Globalization

Public Sub CheckComputerPurchaseLastWeek()
    Dim purchaseRecords As List(Of Dictionary(Of String, Object)) = New List(Of Dictionary(Of String, Object))() From {
        New Dictionary(Of String, Object) From {{"product", "电脑"}, {"purchaseDate", New DateTime(2023, 8, 29)}, },
        New Dictionary(Of String, Object) From {{"product", "电脑"}, {"purchaseDate", New DateTime(2023, 8, 30)}, },
        New Dictionary(Of String, Object) From {{"product", "电脑"}, {"purchaseDate", New DateTime(2023, 9, 5)}, }
    }

    Dim currentDate As
					DateTime
					= DateTime.Now
    Dim lastWeekStart As
					DateTime
					= currentDate.AddDays(-7).Date.ToString("MM/dd/yyyy", CultureInfo.InvariantCulture)

    Dim hasPurchase As
					Boolean
					= False

    For Each record
					In purchaseRecords
        If record("purchaseDate").ToString("MM/dd/yyyy", CultureInfo.InvariantCulture) >= lastWeekStart Then

					hasPurchase
					= True
            Exit For
        End If
    Next

    If hasPurchase Then
        Console.WriteLine("上周有购买电脑")
    Else
        Console.WriteLine("上周没有购买电脑")
    End If
End Sub