How to use C# to access Apex REST Service

Question

I want to use C# to access my own apex rest service in a managed package. I can easily do it in IOS and Android. But in C# I wrote code below, it can not work.

string restQuery = App._instanceUrl + @"/services/apexrest/namespace/myservice";  
string requestMessage = "Account,Contact";  

HttpContent content = new StringContent(Convert.ToBase64String(Encoding.UTF8.GetBytes(requestMessage)));

HttpClient queryClient = new HttpClient();

HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, restQuery);  
request.Headers.Add("Authorization", "OAuth " + App._accessToken);  
request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));  
request.Content = content;  

HttpResponseMessage response = await queryClient.SendAsync(request);  
response.EnsureSuccessStatusCode();  
string result = response.Content.ReadAsStringAsync().Result;    

What's wrong with my code?

Answer 1

I have solved this issue, The request param must be a json format.

//joining together the json format string sample:"{"key":"valus"}";
string requestMessage = "{\"jsonData\":\"" + Convert.ToBase64String(Encoding.UTF8.GetBytes("Account,Contact")) + "\"}";

HttpContent content = new StringContent(requestMessage, Encoding.UTF8, "application/json");

//create url using package name in URL
string restQuery = App._instanceUrl +@"/services/apexrest/namespace/MyService";

//create request message associated with POST verb
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, restQuery);

//return JSON to the caller
request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

//add token to header
request.Headers.Add("Authorization", "Bearer " + App._accessToken);

//add content to HttpRequestMessage;
request.Content = content;

HttpClient putClient = new HttpClient();

//call endpoint async
HttpResponseMessage response = await putClient.SendAsync(request);
response.EnsureSuccessStatusCode();

string result = response.Content.ReadAsStringAsync().Result;

Answer 2

You may want to look at the Force.com Toolkit for .NET as a reference. There are a couple of tutorials which may be useful as well.

Working with Custom SOAP and REST Services in .NET Applications

Consuming Force.com SOAP and REST Web Services from .NET Applications

If you are running into a 401, there's a good chance that your access token has expired. Refresh your access token and try again