VB.NetでMixiボイス 投稿するクラス

ということで、投稿の機能しかないし、元はいろんなとこからかき集めたコードなので公開しますね。
コメントが入ってないのと、そもそも使い方間違ってるかもしれませんので、ご利用は自己責任でｗ

Imports System.Text

Imports System.Net

Imports System.IO

Imports System.Text.RegularExpressions

Imports System.Web
Public Class MixiVoice

    Private Class CustomWebClient

        Inherits WebClient
        Private cookieContainer As CookieContainer = New CookieContainer()
        Protected Overrides Function GetWebRequest(ByVal address As Uri) As WebRequest

            Dim request = MyBase.GetWebRequest(address)

            If (TypeName(request) = "HttpWebRequest") Then

                CType(request, HttpWebRequest).CookieContainer = cookieContainer

            End If

            Return request

        End Function

    End Class
    Private _mixi As CustomWebClient

    Private _proxy As System.Net.WebProxy

    Private _encoding As System.Text.Encoding

    Private _iconurl As String

    Private _NickName As String

    Private _login As Boolean

    ReadOnly Property iconurl() As String

        Get

            Return _iconurl

        End Get

    End Property

    ReadOnly Property NickName() As String

        Get

            Return _NickName

        End Get

    End Property

    Sub New()

        _encoding = System.Text.Encoding.GetEncoding("euc-jp")

        _mixi = New CustomWebClient With {.Encoding = _encoding}

        _login = False

    End Sub
    Function login(ByVal mail As String, ByVal pass As String, Optional ByVal Proxy As String = "", Optional ByVal Proxy_user As String = "", Optional ByVal Proxy_password As String = "") As Boolean

        If _login Then

            Debug.Print("すでにログインしている")

            Return True

        End If

        'Proxyの設定がある場合
        If Proxy <> "" Then

            _proxy = New System.Net.WebProxy(Proxy)

            If Proxy_user <> "" Then

                _proxy.Credentials = New System.Net.NetworkCredential(Proxy_user, Proxy_password)

            End If

        End If

        _mixi.Proxy = _proxy

        Dim para As New System.Collections.Specialized.NameValueCollection

        para.Add("next_url", "/home.pl")

        para.Add("email", mail)

        para.Add("password", pass)

        _mixi.UploadValues("https://mixi.jp/login.pl", para)
        Dim echo = _mixi.DownloadString("https://mixi.jp/recent_voice.pl")

        If InStr(echo, "logout loginForm") > 0 Then

            Return False

        End If

        Dim AccountInfo As System.Text.RegularExpressions.Match = Regex.Match(echo, "src=""(http://profile.img.mixi.jp/photo/member/.+?)"" />\s+(.+?)")

        If AccountInfo.Success Then

            _iconurl = AccountInfo.Groups(1).Value

            _NickName = AccountInfo.Groups(2).Value

        Else

            Return False

        End If

        _login = True

        Return True

    End Function

    Function SendMessage(ByVal msg As String) As Boolean

        If Not _login Then

            Debug.Print("ログインされてないお")

            Return False

        End If
        Dim echo = _mixi.DownloadString("https://mixi.jp/recent_voice.pl")

        If InStr(echo, "logout loginForm") > 0 Then

            Return False

        End If


        Dim postkey = Regex.Match(echo, "id=""post_key"" value=""(.+?)""").Groups(1).Value
        _mixi.Headers(HttpRequestHeader.ContentType) = "application/x-www-form-urlencoded"
        _mixi.UploadString("http://mixi.jp/add_voice.pl", String.Join("&", New String() _

        { _

            "body=" & HttpUtility.UrlEncode(msg, _encoding), _

            "post_key=" & postkey, _

            "redirect=recent_echo" _

        }))

        Return True

    End Function

End Class