Bulk SMS using VB.NET 2008

Goood day,

I have built an SMS application using vb.NET 2008 Express edition...the application can send a single SMS from database (addressbook). Now I need to create a form where I can send to multiple/bulk contacts that are stored from the database. It seems I'm failing somewhere but confused...the contacts should be seperated by a deliminated comma ( ; ) in order to be send.

HINT: If I can manage to add mobile numbers from a database and theN join them with a deliminated commas ( ; ) then it can work

Bellow please find the code I use to send a single SMS....YOUR URGENT ASSISTANCE WILL BE HIGHLY APPRECIATED....

Code:

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Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim MyString As String
        Dim TxUserName As String
        Dim TxPassword As String
        Dim TxMessage As String
        Dim TxNumber As String
        TxUserName = TBUserNameTextBox.Text 'for login purposes
        TxPassword = TBPasswordTextBox.Text ' for login purposes
        TxMessage = TBMessage.Text 'message box

        TxNumber = CellphoneTextBox.Text 'my address textbox where I retrieve the number to send to

        MyString = "http://www.mysiteaddress.net/api/batchmessage.asp?User="
        MyString = MyString & TxUserName & "&Password=" & TxPassword & "&Delivery=No"
        MyString = MyString & "&Message=" & TxMessage & "&Numbers=" & TxNumber & ";"
        MsgBox(readHtmlPage(MyString))
        Me.Close()

    End Sub

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