How to send / receive cURL/API requests in C#

Question

i have problems with my c# programm to send or receive cURL requests to a online telephone system, i hope to get some help there :)

I want to send commands like this:

Answer 1

I prefer using WebClient

WebClient wc = new WebClient();
var buf = wc.UploadValues("https://api.placetel.de/api/test", 
                           new NameValueCollection() { { "api_key", "XXXX" } });
var xml = Encoding.UTF8.GetString(buf);

or HttpClient

HttpClient client = new HttpClient();
var content = new FormUrlEncodedContent(new Dictionary() { 
        { "api_key", "XXXX" } 
});
var resp =  await client.PostAsync("https://api.placetel.de/api/test",content);
var xml = await resp.Content.ReadAsStringAsync();

which have methods easier to use.

BTW, -d (or --data) is a parameter of curl, it is not sent to server

PS: You may also want to read something about ContentType http://www.freeformatter.com/mime-types-list.html