Question

I want to directly capture JSON from an external API in a service layer, return that to a MVC 4 ApiController, and then output the JSON through that ApiController. I’m basically writing a wrapper around another API service because some other actions have to happen at the same time (authentication, etc). The problem is that the JSON gets converted to a string and is passed around as a string in my C# code. This just adds escape characters to the JSON. Is there anyway I can just pass the JSON object around in my C# code? Details of my implementation are below.

In a service layer, I’m consuming an API that provides JSON via the method below.

return new WebClient().DownloadString(url);

Unfortunately this returns a string. As this API is already returning JSON to me this is problematic because lots of escape characters get added to the string.

The JSON should look something like this

[{"Citation":{"Attachments":[{"AttachedPersonIds":null,..."Type":"Record"}]

But instead it now looks like this

"[{\"Citation\":{\"Attachments\":[{\"AttachedPersonIds\":null,...\"Type\":\"Record\"}]"

After I get this string I return it through a couple of methods to an ApiController (which is setup to return JSON) like this.

public class HintsController : ApiController
{
    public string Get(string treeId, string personId)
    {
        return _hintService.GetHints(treeId, personId);
    }
}

I’ve tried to convert the string to a Literal string and tried serializing the string again. Doing this just adds more escape characters and doesn’t solve the problem. I think the problem is with how I’m consuming the initial call because it’s casting it from JSON to a string. But I don’t know how to avoid this.

Thanks in advance for any ideas.

Answer 1

Because the controller returns a string, the JSON formatter is serializing the entire string to a JSON string and escaping the embedded quote characters.

You can do something like this:

public HttpResponseMessage Get()
{
    var resp = new HttpResponseMessage()
    {
        Content = new StringContent("{json here...}")
    };
    resp.Content.Headers.ContentType = 
                  new MediaTypeHeaderValue("application/json");
    return resp;
}

This assumes that you always want to return JSON.