asp.net webapi 的Request如何获取参数

  public class BaseApiController : ApiController
    {
        private HttpRequestBase _request;

        /// 全局Requests对象
        protected HttpRequestBase Requests
        {
            get
            {
                if (_request == null)
                {
                    _request = GetRequest();
                }

                return _request;
            }
        }

｝