无法弄清楚为什么我在我的 jsonp 序列化中得到重复数据

Question

我正在使用我在searching here on SO 中找到的自定义 JsonpResult 类。我已经通读了代码，并且了解它是如何工作的（至少我认为我是这样做的），但是……由于某种原因，当我序列化我的 Object 时，我得到了重复的字符串……为什么会这样?

这是自定义类

/* ****************************************************************************
 *
 * Copyright (c) Microsoft Corporation. All rights reserved.
 *
 * Content of this class was mostly derived from the original
 * JsonResult class in the System.Web.Mvc 2.0 RTM Assembly. This
 * has beeen slightly extended for use with JSONP calls.
 *
 * This software is subject to the Microsoft Public License (Ms-PL).
 * A copy of the license can be found in the license.htm file included
 * in this distribution.
 *
 * You must not remove this notice, or any other, from this software.
 *
 * ***************************************************************************/
namespace System.Web.Mvc
{
    using System;
    using System.Text;
    using System.Web;
    using System.Web.Mvc.Resources;
    using System.Web.Script.Serialization;

    public class JsonpResult : ActionResult
    {

        public JsonpResult() { }

        public Encoding ContentEncoding { get; set; }

        public string ContentType { get; set; }

        public object Data { get; set; }

        public string JsonCallback { get; set; }

        public override void ExecuteResult(ControllerContext context)
        {
            if (context == null)
            {
                throw new ArgumentNullException("context");
            }

            this.JsonCallback = context.HttpContext.Request["jsoncallback"];

            if (string.IsNullOrEmpty(this.JsonCallback))
                this.JsonCallback = context.HttpContext.Request["callback"];

            if (string.IsNullOrEmpty(this.JsonCallback))
                throw new ArgumentNullException("JsonCallback required for JSONP response.");

            HttpResponseBase response = context.HttpContext.Response;

            if (!String.IsNullOrEmpty(ContentType))
            {
                response.ContentType = ContentType;
            }
            else
            {
                response.ContentType = "application/javascript";
            }
            if (ContentEncoding != null)
            {
                response.ContentEncoding = ContentEncoding;
            }
            if (Data != null)
            {
                JavaScriptSerializer serializer = new JavaScriptSerializer();
                response.Write(string.Format("{0}({1});", this.JsonCallback, serializer.Serialize(Data)));
            }
        }
    }

    //extension methods for the controller to allow jsonp.
    public static class ContollerExtensions
    {
        public static JsonpResult Jsonp(this Controller controller, object data)
        {
            JsonpResult result = new JsonpResult();
            result.Data = data;
            result.ExecuteResult(controller.ControllerContext);
            return result;
        }
    }
}

这是我的控制器操作

public class VimeoController : Controller
{

    //
    // GET: /Vimeo/
    public JsonpResult Read()
    {

    Models.ViewModels.JsonViewModel JsonResponse;

        try
        {
            VimeoSharp.APIs.VimeoSimple VimeoSimple = new VimeoSharp.APIs.VimeoSimple();
            // Tell VimeoSharp what channel to pull it's videos from (193328)
            List<VimeoSharp.Video> VimeoList = VimeoSimple.ChannelVideos("193328");

            // Create a viewmodel list of videos to be used.
            // we're only using id and title for this bit.
            List<Models.Pocos.Vimeo> videoList = new List<Models.Pocos.Vimeo>();
            foreach (VimeoSharp.Video record in VimeoList)
            {
                videoList.Add(new Models.Pocos.Vimeo
                {
                    id = 1, //Int32.Parse(record.ID),
                    title = "a" //(record.Title.Length > 26 ? record.Title.Substring(0, 25) + "..." : record.Title)
                });
            };

            JsonResponse = new Models.ViewModels.JsonViewModel
            {
                results = videoList,
                success = true
            };
        }
        catch {
            JsonResponse = new Models.ViewModels.JsonViewModel
            {
                results = null,
                success = false
            };
        }

        // a failed response
        return this.Jsonp(JsonResponse);
    }

}

这是输出结果。

CALLBACK1001({"results":[{"id":1,"title":"a"},{"id":1,"title":"a"},{"id":1, "title":"a"},{"id":1,"title":"a"},{"id":1,"title":"a"},{"id":1,"title ":"a"},{"id":1,"title":"a"},{"id":1,"title":"a"},{"id":1,"title": "a"},{"id":1,"title":"a"},{"id":1,"title":"a"},{"id":1,"title":"a "},{"id":1,"title":"a"},{"id":1,"title":"a"}],"success":true});CALLBACK1001({"results" :[{"id":1,"title":"a"},{"id":1,"title":"a"},{"id":1,"title":"a"}, {"id":1,"title":"a"},{"id":1,"title":"a"},{"id":1,"title":"a"},{" id":1,"title":"a"},{"id":1,"title":"a"},{"id":1,"title":"a"},{"id" :1,"title":"a"},{"id":1,"title":"a"},{"id":1,"title":"a"},{"id":1 ,"title":"a"},{"id":1,"title":"a"}],"success":true});

为什么我的JsonResponse 被序列化了两次？

Answer 1

问题出在你的扩展方法上：

public static class ContollerExtensions
{
    public static JsonpResult Jsonp(this Controller controller, object data)
    {
        JsonpResult result = new JsonpResult();
        result.Data = data;
        //result.ExecuteResult(controller.ControllerContext); <-- Remove this !!!
        return result;
    }
}

注意我评论的那一行。您基本上是两次调用结果。在 ActionResult 上调用 ExecuteResult 方法是 ASP.NET MVC 框架的责任，而不是你的。

另外，如果您在 StackOverflow 上找到此代码，为什么它是 Copyright (c) Microsoft Corporation。保留所有权利。 :-)