.net core api json 时间序列化返回多种场景踩

builder.Services.AddControllers().AddJsonOptions(options =>
{
    options.JsonSerializerOptions.Converters.Add(new MyDateTimeConverter());
    options.JsonSerializerOptions.Converters.Add(new DateTimeNullableConverter());
    options.JsonSerializerOptions.AddContext<MyJsonContext>();//处理aot
});
builder.Services.AddControllers().AddNewtonsoftJson(options =>//install-package Microsoft.AspNetCore.Mvc.NewtonsoftJson
{
    options.SerializerSettings.ContractResolver = new DefaultContractResolver();
    options.SerializerSettings.DateTimeZoneHandling = DateTimeZoneHandling.Utc;  // 设置时区为 UTC)
    options.SerializerSettings.DateFormatString = "yyyy-MM-dd HH:mm:ss";
});

namespace webapi_mes.baseframework.convert
{
    public class MyDateTimeConverter : JsonConverter<DateTime>
    {
        /*         public override DateTime Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
                 {
                     return DateTime.Parse(reader.GetString());
                 }
                 public override void Write(Utf8JsonWriter writer, DateTime value, JsonSerializerOptions options)
                 {
                     writer.WriteStringValue(value.ToString("yyyy-MM-dd HH:mm:ss"));
                 }*/
        /// <summary>
        /// 获取或设置DateTime格式
        /// <para>默认为: yyyy-MM-dd HH:mm:ss</para>
        /// </summary>
        /// 


        public string DateTimeFormat { get; set; } = "yyyy-MM-dd HH:mm:ss";

        public override DateTime Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)//=> DateTime.Parse(reader.GetString());
        {
            //return DateTime.Parse(reader.GetString());
            if (reader.TokenType == JsonTokenType.String)
            {
                if (DateTime.TryParse(reader.GetString(), out DateTime date))
                    return date;
            }
            return reader.GetDateTime();
        }

        public override void Write(Utf8JsonWriter writer, DateTime value, JsonSerializerOptions options)
        //=> writer.WriteStringValue(value.ToString(this.DateTimeFormat));
        {
            writer.WriteStringValue(value.ToString(this.DateTimeFormat));
        }


    }




    public class DateTimeNullableConverter : JsonConverter<DateTime?>
    {
        public override DateTime? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
        {
            return string.IsNullOrEmpty(reader.GetString()) ? default(DateTime?) : DateTime.Parse(reader.GetString());
        }
        public override void Write(Utf8JsonWriter writer, DateTime? value, JsonSerializerOptions options)
        {
            writer.WriteStringValue(value?.ToString("yyyy-MM-dd HH:mm:ss"));
        }
    }
}

参考链接
https://learn.microsoft.com/en-us/dotnet/standard/datetime/system-text-json-support

但是上面的东西无法处理datatable里面的时间格式化

最后应该这样处理

JsonSerializerSettings settings = new JsonSerializerSettings
{
    DateFormatString = "yyyy-MM-dd HH:mm:ss"
};
  JArray obj_row = JArray.FromObject(dataTable, JsonSerializer.Create(settings));//

也可以用如下方法

JsonSerializerSettings settings = new JsonSerializerSettings
{
    DateFormatString = "yyyy-MM-dd HH:mm:ss"
};

// Serialize the DataTable to a JSON string using the custom date format string
string json = JsonConvert.SerializeObject(table, settings);

下面是测试代码

using System;
using System.Data;
using Newtonsoft.Json;

// Create a DataTable with a DateTime column
DataTable table = new DataTable();
table.Columns.Add("Date", typeof(DateTime));

// Add some rows to the table
table.Rows.Add(DateTime.Now);
table.Rows.Add(DateTime.Now.AddDays(1));

// Create a serializer settings object with a custom date format string
JsonSerializerSettings settings = new JsonSerializerSettings
{
    DateFormatString = "yyyy-MM-dd HH:mm:ss"
};

// Serialize the DataTable to a JSON string using the custom date format string
string json = JsonConvert.SerializeObject(table, settings);

// Output the JSON string
Console.WriteLine(json);