private string SMSGlobalData(string username, string password, string source, string destination, string text)
{

      System.Text.StringBuilder postData = new System.Text.StringBuilder("action=sendsms");
      postData.Append("&user=");
      postData.Append(System.Web.HttpUtility.UrlEncode(username));
      postData.Append("&password=");
      postData.Append(System.Web.HttpUtility.UrlEncode(password));
      postData.Append("&from=");
      postData.Append(System.Web.HttpUtility.UrlEncode(source));
      postData.Append("&to=");
      postData.Append(System.Web.HttpUtility.UrlEncode(destination));
      postData.Append("&text=");
      postData.Append(System.Web.HttpUtility.UrlEncode(text));

      return postData.ToString();

}

private string SendSms(string url, string postData)
{

      System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
      byte[] data = encoding.GetBytes(postData);

      HttpWebRequest smsRequest = System.Net.WebRequest.Create(url);
      smsRequest.Method = "POST";
      smsRequest.ContentType = "application/x-www-form-urlencoded";
      smsRequest.ContentLength = data.Length;

      System.IO.Stream smsDataStream = null;
      smsDataStream = smsRequest.GetRequestStream();
      smsDataStream.Write(data, 0, data.Length);
      smsDataStream.Close();

      System.Net.WebResponse smsResponse = smsRequest.GetResponse();

      byte[] responseBuffer = new byte[smsResponse.ContentLength];
      smsResponse.GetResponseStream().Read(responseBuffer, 0, smsResponse.ContentLength - 1);
      smsResponse.Close();

      return encoding.GetString(responseBuffer);

}

<?php  
    $username = 'USERNAME'; 
    $password = 'PASSWORD'; 
    $destination = 'PHONE NUMBER'; 
    $source = 'FROM NAME'; 
    $text = 'SAMPLE TEXT'; 
         
    $content =  'action=sendsms'. 
                '&user='.rawurlencode($username). 
                '&password='.rawurlencode($password). 
                '&to='.rawurlencode($destination). 
                '&from='.rawurlencode($source). 
                '&text='.rawurlencode($text); 
     
    $smsglobal_response = file_get_contents('https://api.smsglobal.com/http-api.php?'.$content); 
     
    //Sample Response 
    //OK: 0; Sent queued message ID: 04b4a8d4a5a02176 SMSGlobalMsgID:6613115713715266  
     
    $explode_response = explode('SMSGlobalMsgID:', $smsglobal_response); 
     
    if(count($explode_response) == 2) { //Message Success 
        $smsglobal_message_id = $explode_response[1]; 
         
        //SMSGlobal Message ID 
        echo $smsglobal_message_id; 
    } else { //Message Failed 
        echo 'Message Failed'.'<br />'; 
         
        //SMSGlobal Response 
        echo $smsglobal_response;     
    } 
?>

$smsGlobalURL = 'https://api.smsglobal.com/http-api.php?';
$query = http_build_query([
'action' => 'sendsms',
'user' => 'USERNAME',
'password' => 'PASSWORD',
'from' => 'SENDER',
'to' => '614XXXXXXXXX',
'text' => 'TEXT MESSAGE HERE'
]);
$smsGlobalURL = $smsGlobalURL.$query;

// create a new curl resource and set options
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $smsGlobalURL);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$output = curl_exec($ch);
curl_close($ch);