VB.NET RowCount不是DataGridView的可访问属性？

Question

制作使用虚拟模式DGV的应用。我无法访问DataGridView的属性RowCount，IDE不会将其显示为有效属性。 MSDN说它是。使用Visual Studio 2017和.NET 4.5.2

这是我的代码。我只是按原样张贴，因为我需要每一行。

Imports System.Text.RegularExpressions
Imports HelperLib.SQLiteModule
Imports System.Data.SQLite

Public Class ProxyTesterView

    Private connString As String = "Data Source=" & My.Application.Info.DirectoryPath & "/data.db3;" & "Version=3;"

    Public Property ProxyDT As DataTable

    Private Sub ProxyTesterView_Load(sender As Object, e As EventArgs) Handles Me.Load
        'Only load proxies if we are not in Design mode!
        If DesignMode = False Then
            Try
                LoadProxiesFromDB()
            Catch ex As SQLite.SQLiteException
                If ex.ErrorCode = 1 Then
                    'DB Doesn't exist, create it!
                    CreateNewDB()
                End If
            End Try
        End If
    End Sub

    Private Sub CreateNewDB()
        Dim sql As String = "CREATE TABLE proxies(ip VARCHAR(15), port VARCHAR(5), valid BOOLEAN, speed VARCHAR(5), countryName VARCHAR(36), PRIMARY KEY (ip, port))"
        CreateDB(My.Application.Info.DirectoryPath & "/data.db3", sql)
    End Sub

    Private Sub LoadProxiesFromDB()
        Dim sql As String = "SELECT ip, port, valid, speed, countryName FROM proxies"
        ProxyDT = GetDataTableFromDB(connString, sql)

    End Sub

    Private Sub AddProxyToDB(proxy As Proxy)
        Using cmd As New SQLiteCommand("INSERT INTO proxies (ip, port, valid, speed, countryName) VALUES (@ip, @port, @valid, @speed, @countryName)")
            cmd.Parameters.AddWithValue("@ip", proxy.IP)
            cmd.Parameters.AddWithValue("@port", proxy.Port)
            cmd.Parameters.AddWithValue("@valid", proxy.IsValid)
            cmd.Parameters.AddWithValue("@speed", proxy.Speed)
            cmd.Parameters.AddWithValue("@countryName", proxy.Country)

            ExecuteNonQuery(connString, cmd)
        End Using
    End Sub

    Private Sub ProxyTesterView_KeyDown(sender As Object, e As KeyEventArgs) Handles Me.KeyDown
        If e.Modifiers = Keys.Control AndAlso e.KeyCode = Keys.V Then
            For Each proxy As Proxy In GetProxiesFromClipboard()
                ProxyDT.Rows.Add(proxy)
            Next
        End If
    End Sub

    Public Function GetProxiesFromClipboard() As List(Of Proxy)
        Dim proxies As New List(Of Proxy)
        For Each line As String In Clipboard.GetText().Split(vbCrLf)
            'Regular Expression for proxy pattern found here: https://superuser.com/questions/582120/regex-pattern-for-proxy
            If Regex.IsMatch(line, "((?:\d{1,3}\.){3}\d{1,3}):(\d+)") Then
                proxies.Add(New Proxy(line))
            End If
        Next
        Return proxies
    End Function

    Private Sub dgvProxies_CellValueNeeded(sender As Object, e As DataGridViewCellValueEventArgs) Handles dgvProxies.CellValueNeeded
        Dim row As DataRow = ProxyDT.Rows(e.RowIndex)
        Select Case dgvProxies.Columns(e.ColumnIndex).Name
            Case "ip"
                e.Value = row.Item("ip")
        End Select
    End Sub
End Class