.NET Framework HTTP clients Sending a POST request with a string payload using System.Net.HttpClient
Example
HttpClient is available through NuGet: Microsoft HTTP Client Libraries.
string requestUri = "http://www.example.com";
string requestBodyString = "Request body string.";
string contentType = "text/plain";
string requestMethod = "POST";
var request = new HttpRequestMessage
{
RequestUri = requestUri,
Method = requestMethod,
};
byte[] requestBodyBytes = Encoding.UTF8.GetBytes(requestBodyString);
request.Content = new ByteArrayContent(requestBodyBytes);
request.Content.Headers.ContentType = new MediaTypeHeaderValue(contentType);
HttpResponseMessage result = client.SendAsync(request).Result;
result.EnsureSuccessStatusCode();
