สอนหน่อยครับให้ vb รับค่าจาก textbox ใน vb แล้วส่งค่าไป fill textbox ที่ web

Private Sub MainPage_Loaded(sender As Object, e As System.Windows.RoutedEventArgs)
    Dim url As String = "http://localhost/myphp/hello.php"
    Dim uri As New Uri(url)
    client = New WebClient()
    client.AllowReadStreamBuffering = True

    AddHandler client.DownloadStringCompleted, AddressOf client_DownloadStringCompleted
    AddHandler client.DownloadProgressChanged, AddressOf client_DownloadProgressChanged

    client.DownloadStringAsync(uri)
    
End Sub

Private Sub client_DownloadStringCompleted(sender As Object, e As DownloadStringCompletedEventArgs)

End Sub

Private Sub client_DownloadProgressChanged(sender As Object, e As DownloadProgressChangedEventArgs)