Coffeehouse - 'System.Net.Http.HttpContent' does not contain a definition for 'ReadAsAsync' and no extension method

Sathyaish Chakravarthy — Fri, 25 Jan 2013 12:41:40 GMT

I made a console app to consume a Web API I just made. The console app code does not compile. It gives me the compilation error:

'System.Net.Http.HttpContent' does not contain a definition for
'ReadAsAsync' and no extension method 'ReadAsAsync' accepting a
first argument of type 'System.Net.Http.HttpContent' could be
found (are you missing a using directive or an assembly reference?)

Here's a test method in which this error occurs.

static IEnumerable GetAllFoos()
{
  using (HttpClient client = new HttpClient())
  {
    client.DefaultRequestHeaders.Add("appkey", "myapp_key");

    var response = client.GetAsync("http://localhost:57163/api/foo").Result;

    if (response.IsSuccessStatusCode)
      return response.Content.ReadAsAsync>().Result.ToList();
  }

  return null;
}

I have used this method and consumed it from an MVC client.

Coffeehouse - 'System.Net.Http.HttpContent' does not contain a definition for 'ReadAsAsync' and no extension method

Sathyaish Chakravarthy — Fri, 25 Jan 2013 12:53:57 GMT

After a long struggle, I found the solution.

Solution: Add a reference to System.Net.Http.Formatting.dll. This assembly is also available in the C:\Program Files\Microsoft ASP.NET\ASP.NET MVC 4\Assemblies folder.

The method ReadAsAsync is an extention method declared in the class HttpContentExtensions, which is in the namespace System.Net.Http in the library System.Net.Http.Formatting.

Reflector came to rescue!

Channel 9 Forums - Coffeehouse - 'System.Net.Http.HttpContent' does not contain a definition for 'ReadAsAsync' and no extension method

Coffeehouse - 'System.Net.Http.HttpContent' does not contain a definition for 'ReadAsAsync' and no extension method

Coffeehouse - 'System.Net.Http.HttpContent' does not contain a definition for 'ReadAsAsync' and no extension method