aspnetcore3.0 Webapi JSON序列化反序列化<Dictionary <string，object>

Question

我正在为项目使用asp.net core 3.0版本。

我这样创建我的webapi：

public IActionResult GetData()
    {
        var sql = "select * from aspnetusers";
        var data = _base.GetDynamicBySql(sql) as List<IDictionary<string, object>>;
        return Ok（data);
    }

运行项目并调用方法，它会给我一个错误信息，就像这样：

    Connection ID "18086456109425491997", Request ID "8000001f-0001-fb00-b63f-84710c7967bb": An unhandled exception was thrown by the application.
System.InvalidCastException: Unable to cast object of type '<GetEnumerator>d__9' to type 'System.Collections.IDictionaryEnumerator'.
   at System.Text.Json.JsonSerializer.HandleDictionary(JsonClassInfo elementClassInfo, JsonSerializerOptions options, Utf8JsonWriter writer, WriteStack& state)
   at System.Text.Json.JsonSerializer.Write(Utf8JsonWriter writer, Int32 originalWriterDepth, Int32 flushThreshold, JsonSerializerOptions options, WriteStack& state)
   at System.Text.Json.JsonSerializer.WriteAsyncCore(Stream utf8Json, Object value, Type inputType, JsonSerializerOptions options, CancellationToken cancellationToken)
   at Microsoft.AspNetCore.Mvc.Formatters.SystemTextJsonOutputFormatter.WriteResponseBodyAsync(OutputFormatterWriteContext context, Encoding selectedEncoding)
   at Microsoft.AspNetCore.Mvc.Formatters.SystemTextJsonOutputFormatter.WriteResponseBodyAsync(OutputFormatterWriteContext context, Encoding selectedEncoding)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResultFilterAsync>g__Awaited|29_0[TFilter,TFilterAsync](ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResultExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.ResultNext[TFilter,TFilterAsync](State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeResultFilters()
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResourceFilter>g__Awaited|24_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeFilterPipelineAsync()

我知道，asp.net核心已删除了newtonsoft.json，并使用System.Text.Json进行了更改。

我这样在我的project.startup文件中使用配置

services.AddControllers().AddNewtonsoftJson(o =>
        {
            o.SerializerSettings.ContractResolver = new Newtonsoft.Json.Serialization.DefaultContractResolver();
        })

但是它仍然不起作用。

该项目可以在asp.net core 2.0中工作，我想知道如何配置我的项目，我想将我的项目设置为默认使用Newtonsoft.Json。