how to make sms gateway vb.net

Imports System.Data
Imports System.IO
Imports System.Configuration
Imports System
Imports System.Net
Imports System.Text

Public Function SendSMS(ByVal User As String, ByVal password As String, ByVal Mobile_Number As String, ByVal Message As String, Optional ByVal MType As String = "N") As String
Dim stringpost As String = "User=" & User & "&passwd=" & password & "&mobilenumber=" & Mobile_Number & "&message=" & Message & "&MTYPE=" & MType
'Response.Write(stringpost)
Dim functionReturnValue As String = Nothing
functionReturnValue = ""

Dim objWebRequest As HttpWebRequest = Nothing
Dim objWebResponse As HttpWebResponse = Nothing
Dim objStreamWriter As StreamWriter = Nothing
Dim objStreamReader As StreamReader = Nothing

Try
Dim stringResult As String = Nothing

objWebRequest = DirectCast(WebRequest.Create("http://Domain name/WebserviceSMS.aspx"), HttpWebRequest)
//domain name: Domain name Replace With Your Domain
objWebRequest.Method = "POST"

' Response.Write(objWebRequest)

' Use below code if you want to SETUP PROXY.
'Parameters to pass: 1. ProxyAddress 2. Port
'You can find both the parameters in Connection settings of your internet explorer.

' If you are in the proxy then Uncomment below lines and enter IP and Port.
' Dim myProxy As New Net.WebProxy("192.168.1.108", 6666)
'myProxy.BypassProxyOnLocal = True
'objWebRequest.Proxy = myProxy

objWebRequest.ContentType = "application/x-www-form-urlencoded"

objStreamWriter = New StreamWriter(objWebRequest.GetRequestStream())
objStreamWriter.Write(stringpost)
objStreamWriter.Flush()
objStreamWriter.Close()

objWebResponse = DirectCast(objWebRequest.GetResponse(),HttpWebResponse)


objWebResponse = DirectCast(objWebRequest.GetResponse(), HttpWebResponse)

objStreamReader = New StreamReader(objWebResponse.GetResponseStream())
stringResult = objStreamReader.ReadToEnd()
objStreamReader.Close()
Return (stringResult)
Catch ex As Exception
Return (ex.ToString)
Finally

If (objStreamWriter IsNot Nothing) Then
objStreamWriter.Close()
End If
If (objStreamReader IsNot Nothing) Then
objStreamReader.Close()
End If
objWebRequest = Nothing
objWebResponse = Nothing

End Try
End Function

Protected Sub btnsubmit_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnsubmit.Click
Dim str As String
str = SendSMS(Trim(User1.Value), Passwd.Value, mobilenumber.Value, message.Value)
Response.Write(str)
End Sub

Imports System.Net
Imports System.Text
Imports System.IO

Module Module1

    Sub Main()

        SendSMS("18479790553", "ToNumber", "I am coming there")

    End Sub
    Sub SendSMS(ByVal FromNumber As String, ByVal ToNumber As String, ByVal SMS As String)

        Dim url As String = "http://www.sendandreceivesms.com/api/"
        Dim request As HttpWebRequest = DirectCast(WebRequest.Create(url), HttpWebRequest)
        request.Method = "POST"
        Dim postData As String = "FromNumber=" & FromNumber
        postData += "&"
        postData += "ToNumber=" & ToNumber
        postData += "&"
        postData += "SMS=" & SMS
        Dim byteArray As Byte() = Encoding.UTF8.GetBytes(postData)
        request.ContentType = "application/x-www-form-urlencoded"
        request.Headers.Add("APIToken", "GoOu9H0h9G")'get your new API token at https://www.sendandreceivesms.com
        request.ContentLength = byteArray.Length
        Dim dataStream As Stream = request.GetRequestStream()
        dataStream.Write(byteArray, 0, byteArray.Length)
        dataStream.Close()
        Dim response As WebResponse = request.GetResponse()
        dataStream = response.GetResponseStream()
        Dim reader As New StreamReader(dataStream)
        Dim responseFromServer As String = reader.ReadToEnd() 'Log This in DB, Queue msgs that failed so that they can be sent again when console app runs
        reader.Close()
        dataStream.Close()
        response.Close()
    End Sub

End Module

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