Question

I want to call the google url shortner API from my C# Console Application, the request I try to implement is:

POST https://www.googleapis.com/urlshortener/v1/url

Content-Type: application/json

{“longUrl”: “http://www.google.com/“}

When I try to use this code:

using System.Net;
using System.Net.Http;
using System.IO;

and the main method is:

static void Main(string[] args)
{
    string s = "http://www.google.com/";
    var client = new HttpClient();

    // Create the HttpContent for the form to be posted.
    var requestContent = new FormUrlEncodedContent(new[] {new KeyValuePair<string, string>("longUrl", s),});

    // Get the response.            
    HttpResponseMessage response = client.Post("https://www.googleapis.com/urlshortener/v1/url",requestContent);

    // Get the response content.
    HttpContent responseContent = response.Content;

    // Get the stream of the content.
    using (var reader = new StreamReader(responseContent.ContentReadStream))
    {
        // Write the output.
        s = reader.ReadToEnd();
        Console.WriteLine(s);
    }
    Console.Read();
}

I get the error code 400: This API does not support parsing form-encoded input.
I don’t know how to fix this.

Answer 1

you can check the code below (made use of System.Net).
You should notice that the contenttype must be specfied, and must be “application/json”; and also the string to be send must be in json format.

using System;
using System.Net;

using System.IO;
namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            var httpWebRequest = (HttpWebRequest)WebRequest.Create("https://www.googleapis.com/urlshortener/v1/url");
            httpWebRequest.ContentType = "application/json";
            httpWebRequest.Method = "POST";

            using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
            {
                string json = "{\"longUrl\":\"http://www.google.com/\"}";
                Console.WriteLine(json);
                streamWriter.Write(json);
            }

            var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
            using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
            {
                var responseText = streamReader.ReadToEnd();
                Console.WriteLine(responseText);
            }

        }

    }
}