Newtonsoft.Json 指定某个属性使用特定的日期格式

Intro

Newtonsoft.Json 是 .NET 下最受欢迎 JSON 操作库，原为 JSON.Net 后改名为 Newtonsoft.Json，之前一直推荐大家使用，除了性能好之外，主要是功能丰富，基本满足所有的可能用到的场景（不区分小写，现在还不行，，）。

遇到这样一个需求，全局使用一种时间格式，某些属性使用特殊的时间格式，这里以一个日期为例

Solution

解决办法：自定义一个 Converter，针对某一个属性使用，DateTimeFormatConverter源码:

using Newtonsoft.Json.Converters;

namespace WeihanLi.Common.Json
{
  public class DateTimeFormatConverter : IsoDateTimeConverter
  {
    public DateTimeFormatConverter(string format)
    {
      DateTimeFormat = format;
    }
  }
}

在需要设置格式的属性上设置 Converter https://github.com/WeihanLi/ActivityReservation/blob/dev/ActivityReservation.Helper/ViewModels/ReservationViewModel.cs#L8

[Display(Name = "预约日期")]
[JsonConverter(typeof(DateTimeFormatConverter), "yyyy-MM-dd")]
public DateTime ReservationForDate { get; set; }

请求 api 地址 https://reservation.weihanli.xyz/api/Reservation?pageNumber=1&pageSize=5,返回的数据如下所示：

{
    "Data": [
        {
            "ReservationForDate": "2019-06-10",
            "ReservationForTime": "08:00~09:50",
            "ReservationPersonPhone": "123****0112",
            "ReservationPersonName": "儿**",
            "ReservationUnit": "51",
            "ReservationPlaceName": "多媒体工作室",
            "ReservationActivityContent": "62",
            "ReservationId": "f7ab9128-0977-4fd8-9b1a-92648228b397",
            "ReservationTime": "2019-06-09 05:19:11",
            "ReservationStatus": 1
        },
        {
            "ReservationForDate": "2019-06-12",
            "ReservationForTime": "10:00-12:00",
            "ReservationPersonPhone": "133****3541",
            "ReservationPersonName": "试**",
            "ReservationUnit": "ss",
            "ReservationPlaceName": "多媒体工作室",
            "ReservationActivityContent": "ss",
            "ReservationId": "6c145aea-dc14-4ed9-a47f-48c0b79f7601",
            "ReservationTime": "2019-06-11 12:45:14",
            "ReservationStatus": 0
        },
        {
            "ReservationForDate": "2019-06-17",
            "ReservationForTime": "14:00-16:00",
            "ReservationPersonPhone": "138****3883",
            "ReservationPersonName": "大**",
            "ReservationUnit": "1",
            "ReservationPlaceName": "多媒体工作室",
            "ReservationActivityContent": "1",
            "ReservationId": "cebea7bf-44b1-4565-8cdd-78b6156c5f4d",
            "ReservationTime": "2019-06-10 02:52:18",
            "ReservationStatus": 1
        },
        {
            "ReservationForDate": "2019-06-17",
            "ReservationForTime": "08:00-10:00",
            "ReservationPersonPhone": "132****4545",
            "ReservationPersonName": "冷**",
            "ReservationUnit": "技术部",
            "ReservationPlaceName": "多媒体工作室",
            "ReservationActivityContent": "技术部培训",
            "ReservationId": "07f6f8fd-f232-478e-9a94-de0f5fa9b4e9",
            "ReservationTime": "2019-06-10 01:44:52",
            "ReservationStatus": 2
        },
        {
            "ReservationForDate": "2019-06-22",
            "ReservationForTime": "10:00~11:50",
            "ReservationPersonPhone": "132****3333",
            "ReservationPersonName": "测**",
            "ReservationUnit": "测试",
            "ReservationPlaceName": "多媒体工作室",
            "ReservationActivityContent": "测试",
            "ReservationId": "27d0fb7a-ce14-4958-8636-dd10e5526083",
            "ReservationTime": "2019-06-18 10:57:06",
            "ReservationStatus": 1
        }
    ],
    "PageNumber": 1,
    "PageSize": 5,
    "TotalCount": 18,
    "PageCount": 4,
    "Count": 5
}

可以看到 ReservationForDate 序列化之后返回的格式如我们指定的格式了~