diff --git a/TsinghuaNet/MainViewModel.vb b/TsinghuaNet/MainViewModel.vb
index 30f0546..b442a2b 100644
--- a/TsinghuaNet/MainViewModel.vb
+++ b/TsinghuaNet/MainViewModel.vb
@@ -103,33 +103,29 @@ Class MainViewModel
         End Set
     End Property
 
-    Private auth4 As AuthHelper
-    Private auth6 As AuthHelper
+    Private auth4 As Auth4Helper
+    Private auth6 As Auth6Helper
     Private net As NetHelper
+    Private Function InitHelper(Of T As {New, NetHelperBase})(ByRef helper As T) As T
+        If helper Is Nothing Then
+            helper = New T()
+        End If
+        UpdateHelper(helper)
+        Return helper
+    End Function
+    Private Sub UpdateHelper(helper As NetHelperBase)
+        helper.Username = Username
+        helper.Password = Password
+    End Sub
     Public ReadOnly Property Helper As IConnect
         Get
             Select Case State
                 Case NetState.Auth4
-                    If auth4 Is Nothing Then
-                        auth4 = AuthHelper.CreateAuth4Helper(Username, Password)
-                    Else
-                        UpdateHelper(auth4)
-                    End If
-                    Return auth4
+                    Return InitHelper(auth4)
                 Case NetState.Auth6
-                    If auth6 Is Nothing Then
-                        auth6 = AuthHelper.CreateAuth6Helper(Username, Password)
-                    Else
-                        UpdateHelper(auth6)
-                    End If
-                    Return auth6
+                    Return InitHelper(auth6)
                 Case NetState.Net
-                    If net Is Nothing Then
-                        net = New NetHelper(Username, Password)
-                    Else
-                        UpdateHelper(net)
-                    End If
-                    Return net
+                    Return InitHelper(net)
                 Case Else
                     Return Nothing
             End Select
@@ -178,11 +174,6 @@ Class MainViewModel
         End Get
     End Property
 
-    Private Sub UpdateHelper(helper As NetHelperBase)
-        helper.Username = Username
-        helper.Password = Password
-    End Sub
-
     Public Sub DisposeHelpers()
         net?.Dispose()
         auth4?.Dispose()
diff --git a/TsinghuaNet/Settings.vb b/TsinghuaNet/Settings.vb
index 82e84d0..7cccb90 100644
--- a/TsinghuaNet/Settings.vb
+++ b/TsinghuaNet/Settings.vb
@@ -8,14 +8,65 @@ Class Settings
     Inherits XmlSettings
     <Settings("name")>
     Public Property Username As String
-    <Settings("password")>
+    <Settings("password", ConverterType:=GetType(PasswordConverter))>
     Public Property Password As String
-    <Settings("state")>
+    Class PasswordConverter
+        Implements ISimpleConverter
+        Public Function Convert(value As Object) As Object Implements ISimpleConverter.Convert
+            Return Encoding.ASCII.GetString(System.Convert.FromBase64String(If(value, String.Empty)))
+        End Function
+        Public Function ConvertBack(value As Object) As Object Implements ISimpleConverter.ConvertBack
+            Return System.Convert.ToBase64String(Encoding.ASCII.GetBytes(value))
+        End Function
+    End Class
+    <Settings("state", ConverterType:=GetType(StateConverter))>
     Public Property State As NetState
-    <Settings("more")>
+    Class StateConverter
+        Implements ISimpleConverter
+        Public Function Convert(value As Object) As Object Implements ISimpleConverter.Convert
+            Dim temp As NetState
+            If [Enum].TryParse(value, temp) Then
+                Return temp
+            Else
+                Return NetState.Unknown
+            End If
+        End Function
+        Public Function ConvertBack(value As Object) As Object Implements ISimpleConverter.ConvertBack
+            Return value.ToString()
+        End Function
+    End Class
+    <Settings("more", ConverterType:=GetType(BoolConverter))>
     Public Property MoreInf As Boolean
-    <Settings("language")>
+    Class BoolConverter
+        Implements ISimpleConverter
+        Public Function Convert(value As Object) As Object Implements ISimpleConverter.Convert
+            Dim moreinfResult As Boolean
+            If Boolean.TryParse(value, moreinfResult) Then
+                Return moreinfResult
+            Else
+                Return False
+            End If
+        End Function
+        Public Function ConvertBack(value As Object) As Object Implements ISimpleConverter.ConvertBack
+            Return value.ToString()
+        End Function
+    End Class
+    <Settings("language", ConverterType:=GetType(LanguageConverter))>
     Public Property Language As CultureInfo
+    Class LanguageConverter
+        Implements ISimpleConverter
+        Public Function Convert(value As Object) As Object Implements ISimpleConverter.Convert
+            Try
+                Return If(value Is Nothing, Nothing, New CultureInfo(value.ToString()))
+            Catch ex As Exception
+                WriteException(ex)
+                Return Nothing
+            End Try
+        End Function
+        Public Function ConvertBack(value As Object) As Object Implements ISimpleConverter.ConvertBack
+            Return CType(value, CultureInfo)?.Name
+        End Function
+    End Class
     Private Const logPath As String = "log.xml"
     Public Sub New()
         Username = String.Empty
@@ -44,43 +95,4 @@ Class Settings
     Public Overloads Sub Save()
         Save(logPath)
     End Sub
-    Protected Overrides Function ChangeType(name As String, value As Object, conversionType As Type) As Object
-        Select Case name
-            Case "password"
-                Return Encoding.ASCII.GetString(Convert.FromBase64String(If(value, String.Empty)))
-            Case "state"
-                Dim temp As NetState
-                If [Enum].TryParse(value, temp) Then
-                    Return temp
-                Else
-                    Return NetState.Unknown
-                End If
-            Case "more"
-                Dim moreinfResult As Boolean
-                If Boolean.TryParse(value, moreinfResult) AndAlso moreinfResult Then
-                    Return True
-                Else
-                    Return False
-                End If
-            Case "language"
-                Try
-                    Return If(value Is Nothing, Nothing, New CultureInfo(value.ToString()))
-                Catch ex As Exception
-                    WriteException(ex)
-                    Return Nothing
-                End Try
-            Case Else
-                Return value
-        End Select
-    End Function
-    Protected Overrides Function ChangeBackType(name As String, value As Object, conversionType As Type) As Object
-        Select Case name
-            Case "password"
-                Return Convert.ToBase64String(Encoding.ASCII.GetBytes(value))
-            Case "language"
-                Return CType(value, CultureInfo)?.Name
-            Case Else
-                Return value.ToString()
-        End Select
-    End Function
 End Class
diff --git a/TsinghuaNet/TsinghuaNet.vbproj b/TsinghuaNet/TsinghuaNet.vbproj
index c77dbde..2c2160f 100644
--- a/TsinghuaNet/TsinghuaNet.vbproj
+++ b/TsinghuaNet/TsinghuaNet.vbproj
@@ -76,11 +76,11 @@
     <StartupObject>TsinghuaNet.Program</StartupObject>
   </PropertyGroup>
   <ItemGroup>
-    <Reference Include="Berrysoft.Console, Version=1.0.112.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\packages\Berrysoft.Console.1.0.112-preview2\lib\net472\Berrysoft.Console.dll</HintPath>
+    <Reference Include="Berrysoft.Console, Version=1.0.140.0, Culture=neutral, processorArchitecture=MSIL">
+      <HintPath>..\packages\Berrysoft.Console.1.0.140-preview3\lib\net472\Berrysoft.Console.dll</HintPath>
     </Reference>
-    <Reference Include="Berrysoft.Tsinghua.Net, Version=1.0.112.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\packages\Berrysoft.Tsinghua.Net.1.0.112-preview2\lib\net472\Berrysoft.Tsinghua.Net.dll</HintPath>
+    <Reference Include="Berrysoft.Tsinghua.Net, Version=1.0.140.0, Culture=neutral, processorArchitecture=MSIL">
+      <HintPath>..\packages\Berrysoft.Tsinghua.Net.1.0.140-preview3\lib\net472\Berrysoft.Tsinghua.Net.dll</HintPath>
     </Reference>
     <Reference Include="PresentationFramework.Aero" />
     <Reference Include="System.Core" />
diff --git a/TsinghuaNet/packages.config b/TsinghuaNet/packages.config
index 1937bf2..cbd42c2 100644
--- a/TsinghuaNet/packages.config
+++ b/TsinghuaNet/packages.config
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="Berrysoft.Console" version="1.0.112-preview2" targetFramework="net472" />
-  <package id="Berrysoft.Tsinghua.Net" version="1.0.112-preview2" targetFramework="net472" />
+  <package id="Berrysoft.Console" version="1.0.140-preview3" targetFramework="net472" />
+  <package id="Berrysoft.Tsinghua.Net" version="1.0.140-preview3" targetFramework="net472" />
   <package id="System.Json" version="4.5.0" targetFramework="net472" />
 </packages>
\ No newline at end of file