上传大文件时提示Maximum request length exceeded错误的解决方法

[HttpPost]
        public HttpResponseMessage UploadFile()
        {
            HttpResponseMessage result = null;
            var httpRequest = Request;
           try
                {

                    var content = httpRequest.Content.ReadAsStringAsync().Result;

                }
                catch (Exception ex)
                {
                    logger.Error($"上传文件失败：{JsonConvert.SerializeObject(ex)}");

                    result = Request.CreateResponse(HttpStatusCode.OK, "error:" + ex.Message);
                }
return result;
        }

上传文件大小iis有限制，需要修改配置：

<system.webServer>
   <security>
      <requestFiltering>
         <requestLimits maxAllowedContentLength="1073741824" /></requestFiltering>  
   </security>
</system.webServer>

单位为byte 1024*1024*1024=1073741824=1G