Sending SMS using ASP.NET (C#) through HTTP

Hi all,

I found this source code at and I am wondering whether this code might really work of I want to send an SMS message to the given phone number with the given content.

The source code of the example application is structured in the following way:

In this file there are page builder asp elements (text boxes, labels, etc.).

Page_Load(...): does some basic settings.
buttonSendOnClick(...): creates and sends the sms from the given data.

Description of the process depicted in Figure 1 above:

Step 1: Create the HTML form
In the smssend.aspx file, you create the form that requests the sms data. The Internet user fills in the necessaries. Label and textbox pairs will be displayed. Labels identify the requested data for the Internet user, and they will type it in textboxes. The user will be asked to fill in the Recipient and Message text fields. A multiline textbox is used to inform the Internet user about error(s) or result(s) of sending the message. At first, the error box will be invisible (it will be set in the smssend.aspx.cs file).


Compose a message:


In the "protected void Page_Load(object sender, EventArgs e)" procedure (in smssend.aspx.cs), you set the width of textboxes and the error box height in rows. The text of the error box is red, and the first is invisible and empty. If ? using the net browser ? the page is downloaded for the first time, fill in the recipient and message boxes with predefined texts.

protected void Page_Load(object sender, EventArgs e)
textboxRecipient.Width = 400;
textboxMessage.Width = 450;
textboxMessage.Rows = 10;
textboxError.Width = 400;
textboxError.Rows = 5;

textboxError.ForeColor = System.Drawing.Color.Red;
textboxError.Visible = false;
textboxError.Text = "";

if (!Page.IsPostBack)
textboxRecipient.Text = "+441234567";
textboxMessage.Text = "Hello World!";

Step 2: Processing data coming from the HTML form
After filling in the fields and clicking the Send button , the ASP server receives the information about the form. In the smssend.aspx.cs file, the "protected void buttonSendOnClick(object sender, EventArgs e)" procedure is called. At the beginning of the procedure, check the data of the textbox fields. The Recipient box is mandatory. If it is empty, the processing will be aborted, and the Internet user will be shown the error. If the checking is successful, you will create the URL that will tell the Ozeki NG - SMS Gateway Server the requested information. We need the following: the URL of the computer running Ozeki NG - SMS Gateway Server the default URL is ( means that Ozeki NG - SMS Gateway Server is installed on the same computer on which the ASP.NET script is running), the port number on which the server listens, the username, which is authorized to log in to the Ozeki NG - SMS Gateway Server and to send messages (the default username is admin), the user's password (the default is abc123), the message type (the default is SMS:TEXT), the recipient and the message data. The following values must be URL-encoded: username, password, recipient and message data.

protected void buttonSendOnClick(object sender, EventArgs e)
//fields are required to be filled in:
if (textboxRecipient.Text == "")
textboxError.Text += "Recipient(s) field must not be empty!
textboxError.Visible = true;

//we are creating the necessary URL string:
string ozSURL = ""; //where Ozeki NG SMS Gateway is running
string ozSPort = "9501"; //port number where Ozeki NG SMS Gateway is listening
string ozUser = HttpUtility.UrlEncode("admin"); //username for successful login
string ozPassw = HttpUtility.UrlEncode("abc123"); //user's password
string ozMessageType = "SMS:TEXT"; //type of message
string ozRecipients = HttpUtility.UrlEncode(textboxRecipient.Text); //who
will get the message
string ozMessageData = HttpUtility.UrlEncode(textboxMessage.Text); //body
of message

string createdURL = ozSURL + ":" + ozSPort + "/httpapi" +
"?action=sendMessage" +
"&username=" + ozUser +
"&password=" + ozPassw +
"&messageType=" + ozMessageType +
"&recipient=" + ozRecipients +
"&messageData=" + ozMessageData;

Step 3: Sending a request to the SMS Gateway and receiving the answer
In the code you send a request to the Ozeki NG - SMS Gateway Server with the data of the message. It will create an SMS and send it to the recipient (mobile user) using a GSM modem/phone (if the given data is correct) and send you the result.
You create a request to the Ozeki NG - SMS Gateway Server at the URL created above. When it is done, you will receive a response from the Ozeki NG - SMS Gateway Server. The information will be retrieved from it and shown to the Internet user. Whatever problem you have, it is because the Ozeki NG - SMS Gateway Server is not running at the moment of sending data.

protected void buttonSendOnClick(object sender, EventArgs e)
//Create the request and send data to Ozeki NG SMS Gateway Server by
HTTP connection
HttpWebRequest myReq = (HttpWebRequest)WebRequest.Create(createdURL);

//Get response from Ozeki NG SMS Gateway Server and read the answer
HttpWebResponse myResp = (HttpWebResponse)myReq.GetResponse();
System.IO.StreamReader respStreamReader = new System.IO.StreamReader(myResp.GetResponseStream());
string responseString = respStreamReader.ReadToEnd();

//inform the user
textboxError.Text = responseString;
textboxError.Visible = true;
catch (Exception)
//if sending request or getting response is not successful, Ozeki NG - SMS Gateway Server may not be running
textboxError.Text = "Ozeki NG SMS Gateway Server is not running!";
textboxError.Visible = true;

Thank you for your time and answer

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