WebApi接口返回json,xml,text纯文本等

[Route("api/Message/MessageList/")]
[HttpGet]
public HttpResponseMessage MessageList()
{
ResponseResult obj = new ResponseResult();
var pageData = Ydt.ExtLib.DataTableHelper.DataTableToList<ViewGoodChart>(result.Tables[]);
List<JObject> list = new List<JObject>();
foreach (var item in pageData)
{
list.Add(JObject.FromObject(item));
}
obj.info = list;
obj.status = true;
obj.message = "获取成功";
JsonStr = JsonConvert.SerializeObject(obj);
//返回纯文本text/plain ,返回json application/json ,返回xml text/xml
HttpResponseMessage result = new HttpResponseMessage { Content = new StringContent(JsonStr, Encoding.GetEncoding("UTF-8"), "application/json") };
return result;
}