C# 在UWP中将对象列表保存为JSON

有人能告诉我如何在UWP中将对象数组序列化为json保存吗？我试过这种方法，但效果不好。文件长度后缺少文本。我使用的是Newtonsoft.Json

代码-

private void btn_saveModel_Click(object sender, RoutedEventArgs e)
    {

        SaveModel();

    }

    StorageFile file;

    private async Task openSaveFile()
    {
        var savePicker = new Windows.Storage.Pickers.FileSavePicker();
        savePicker.SuggestedStartLocation = Windows.Storage.Pickers.PickerLocationId.DocumentsLibrary;
        // Dropdown of file types the user can save the file as
        savePicker.FileTypeChoices.Add("JSON", new List<string>() { ".json" });
        savePicker.FileTypeChoices.Add("Plain Text", new List<string>() { ".txt" });
        // Default file name if the user does not type one in or select a file to replace
        savePicker.SuggestedFileName = "New Data";

        StorageFile file = await savePicker.PickSaveFileAsync();

        this.file = file;
    }

    private void SaveModel()
    {
        var task = openSaveFile();
        Task.WhenAll(task);
        if (file != null)
        {
            var handle = file.CreateSafeFileHandle(options: FileOptions.RandomAccess);
            var stream = new FileStream(handle, FileAccess.ReadWrite);
            var writer = new StreamWriter(stream);

            JsonSerializer serializer = new JsonSerializer();
            serializer.Serialize(writer, LoadedIntents);

        }
    }

]

保存后，即使没有改变，我得到这个

[ { “标签”：“问候语”， “模式”：[ “问候”， “嗨”， “嘿”， “有人在吗？”， “你好”， “干草” ], “回应”：[ “你好”， “嗨”， “你好” ] }, { “标签”：“再见”， “模式”：[ “再见”， “回头见”， “再见” ], “回应”：[ “回头见”， “祝你有愉快的一天”， “再见！再来” ] }, { “标签”：“谢谢”， “模式”：[ “谢谢”， “谢谢你”， “这很有帮助”， “谢谢你的帮助” ], “回应”：[ “很乐意帮忙！”， “随时！”， “我的荣幸”， “不客气！” ] }, { “标签”：“关于”， “模式”：[ “你是谁？”， “你是干什么的？”， “你是谁？” ], “回应”：[ “I.m.Osumen，你的虚拟朋友”， “我是奥斯曼，一个拥有人工智能的朋友” ] }, { “标签”：“名称”， “模式”：[ “你叫什么名字”， “我该怎么称呼你”， “你叫什么名字？” ], “回应”：[ “你可以叫我男人。”， “我是男人！”， “叫我男人就行了” ] }, { “标签”：“帮助”， “模式”：[ “你能帮我吗？”， “请帮帮我”， “你能帮忙吗？”， “你能为我做些什么？”， “我需要支持”， “我需要帮助”， “请支持我” ], “回应”：[ “告诉我怎样才能帮助你”，“把你的问题告诉我”

我做错了什么？

当您使用时，您使用的是一种异步方法，它试图立即完成

任务，如果没有，它应该继续执行代码，以便在后台工作时处理其他事情

但是，当您使用诸如：
wait Task.WhenAll（Task）；
之类的关键字时，会发生一些不同的情况

wait关键字告诉编译器“您应该立即尝试完成此任务，如果它不能及时完成，请继续工作，但我会耐心等待您完成它。”

无需等待
任务。当所有
如果
打开保存文件
未完成并立即返回时，
保存模型
将继续执行其代码，而不是耐心等待。这就是为什么有时你会从
保存模型中得到半生不熟的结果，因为你需要恢复因为你不等待结果，所以在它完成之前就结束了

您可能打算使用的是非异步版本的
任务。WhenAll
，它强制等待任务完成，没有结果就无法继续。
您忘记等待
任务。WhenAll（任务）
。您也没有刷新StreamWriter。这不是一个真正的UWP问题；问题完全在与UWP无关的代码中。谢谢您…我对此还是新手…非常感谢您..在我添加Wait并使方法异步后，它起了作用。刷新stream writer后，长度问题也得到了纠正。
[
   {"tag": "greeting",
    "patterns": ["Hi", "Hey", "Is anyone there?", "Hello", "Hay"],
    "responces": ["Hello", "Hi", "Hi there"]
   },
   {"tag": "goodbye",
    "patterns": ["Bye", "See you later", "Goodbye"],
    "responces": ["See you later", "Have a nice day", "Bye! Come back again"]
   },
   {"tag": "thanks",
    "patterns": ["Thanks", "Thank you", "That's helpful", "Thanks for the help"],
    "responces": ["Happy to help!", "Any time!", "My pleasure", "You're most welcome!"]
   },
   {"tag": "about",
    "patterns": ["Who are you?", "What are you?", "Who you are?" ],
    "responces": ["I.m Osumen, your virtual friend", "I'm Osumen, a Friend who has an Artificial Intelligence"]
   },
   {"tag": "name",
   "patterns": ["what is your name", "what should I call you", "whats your name?"],
   "responces": ["You can call me Osumen.", "I'm Osumen!", "Just call me as Osumen"]
   },
   {"tag": "help",
   "patterns": ["Could you help me?", "give me a hand please", "Can you help?", "What can you do for me?", "I need a support", "I need a help", "support me please"],
   "responces": ["Tell me how can assist you", "Tell me your problem to assist you", "Yes Sure, How can I support you"]
   },
   {"tag": "complaint",
   "patterns": ["have a complaint", "I want to raise a complaint", "there is a complaint about a service"],
   "responces": ["Please provide us your complaint in order to assist you", "Please mention your complaint, we will reach you and sorry for any inconvenience caused"]
   }