->First you need Purchas from Value-First SMS Provider to send SMS.
->using XML API to send SMS from in web application
->develop the GUI for sending SMS.
code sample of ASPX
------------
<%@Page Language=”C#”AutoEventWireup=”true”CodeBehind=”SMS.aspx.cs”Inherits=”SMSTest.SMS” %>
<!DOCTYPE htmlPUBLIC“-//W3C//DTD XHTML 1.0 Transitional//EN”“http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>
<html xmlns=”http://www.w3.org/1999/xhtml”>
<head runat=”server”>
<title></title>
</head>
<body style=”height: 313px”>
<form id=”form1″runat=”server”>
<div>
<h1> Sending SMS Application </h1>
</div>
<p>
<asp:LabelID=”lblTo”runat=”server”Text=”To:-”></asp:Label>
</p>
<asp:TextBoxID=”txtTo”runat=”server”></asp:TextBox>
<p>
<asp:LabelID=”lblFrom”runat=”server”Text=”From:-”></asp:Label>
</p>
<asp:TextBoxID=”txtFrom”runat=”server”Width=”128px”></asp:TextBox>
<p>
<asp:LabelID=”lblBody”runat=”server”Text=”SMS Message:-”></asp:Label>
</p>
<p>
<asp:TextBoxID=”txtBody” TextMode=”MultiLine”runat=”server”></asp:TextBox>
</p>
<asp:ButtonID=”btnSend”runat=”server”onclick=”btnSend_Click”Text=”Send”/>
<p>
<asp:Label ID=”lblResult”runat=”server”Text=” “></asp:Label>
</p>
</form>
</body>
</html>
Code sample of CS
--------------
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;
using System.Net;
using System.Text;
namespace SMSTest
{
public partial class SMS : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void btnSend_Click(object sender, EventArgs e)
{
System.Net.WebClient webClient = new System.Net.WebClient();
string postData = “usr=yourapiusername&pwd=yourapipwd&from= “ + txtFrom.Text + “&to=” + txtTo.Text +“&type=text” + txtBody.Text;
webClient.Headers.Add(“Content-Type”,“application/x-www-form-urlencoded”);
lblResult.Text = webClient.UploadString(“http://api.myvaluefirst.com/psms/servlet/psms.Eservice2?data=<?xml%20version=\”1.0\”%20encoding=\”ISO-8859-1\”?><!DOCTYPE%20MESSAGE%20SYSTEM%20\”http://127.0.0.1/psms/dtd/message.dtd\”%20><MESSAGE><USER%20USERNAME=\”Your SMS API Username” + “\”%20PASSWORD=\”Your SMS API Password” + “\”/><SMS%20UDH=\”0\”%20CODING=\”1\”%20TEXT=\”" + txtBody.Text + “\”%20PROPERTY=\”0\”%20ID=\”1\”><ADDRESS%20FROM=\”919903013543\”%20TO=\”" + txtTo.Text + “\”%20SEQ=\”1\”%20TAG=\”some%20clientside%20random%20data\”%20/></SMS></MESSAGE>&action=send”, postData);
}
}
}
Also good article here: <http://www.c-sharpcorner.com/uploadfile/scottlysle/textmsgtocellphone12112006002339am/textmsgtocellphone.aspx>