I want to Convert a PHP SMS API code to ASP.net C# code

Question

<?php    

$contacts = array(  "233XXXXXXXXX" => "John",  "233XXXXXXXXX" => "Baptist",   );

foreach($contacts as $number => $name){  

$url = "http://api.mytxtbox.com/v3/messages/send?".  

"From=Dawunis"  

."&To=$number"  

."&Content=".urlencode("Dear $name, enjoy a up to 50% discount on all Leather Bags. Use coupon code FIFTY-OFF to checkout. http://www.dawunisboutique.com.")  

."&ClientId=btgpchyh"  

."&ClientSecret=gafzdfso"  

."&RegisteredDelivery=true";   

$curl = curl_init();   

curl_setopt_array($curl, array(  CURLOPT_URL => $url,  CURLOPT_RETURNTRANSFER => true,  CURLOPT_CUSTOMREQUEST => "GET",  ));   

$response = curl_exec($curl);  $err = curl_error($curl);   curl_close($curl);   

if ($err) {  echo "cURL Error #:" . $err;  } 

else {  echo $response;  }  } 

?>