Web Owin:如何“重新映射/重命名”由BaseValidatingContext.SetError创建的json响应中的字段

using System;
using System.Threading.Tasks;
using Microsoft.Owin;

public class RenameFieldMiddleware : OwinMiddleware
{
    public RenameFieldMiddleware(OwinMiddleware next) : base(next)
    {
    }

    public override async Task Invoke(IOwinContext context)
    {
        var originalResponseStream = context.Response.Body;
        var responseBuffer = new MemoryStream();
        context.Response.Body = responseBuffer;

        await Next.Invoke(context);

        responseBuffer.Seek(0, SeekOrigin.Begin);
        var responseBody = await new StreamReader(responseBuffer).ReadToEndAsync();
        responseBuffer.Seek(0, SeekOrigin.Begin);

        // 解析JSON响应为对象
        var responseObject = JsonConvert.DeserializeObject(responseBody);

        // 修改字段名
        if (responseObject != null && responseObject.error != null)
        {
            responseObject.errorMessage = responseObject.error;
            responseObject.error = null;
        }

        // 将修改后的对象转换回JSON格式
        var modifiedResponseBody = JsonConvert.SerializeObject(responseObject);

        // 将修改后的JSON响应写回到响应流中
        var modifiedResponseBytes = Encoding.UTF8.GetBytes(modifiedResponseBody);
        await responseBuffer.WriteAsync(modifiedResponseBytes, 0, modifiedResponseBytes.Length);
        responseBuffer.Seek(0, SeekOrigin.Begin);

        // 恢复原始的响应流
        context.Response.Body = originalResponseStream;
        await responseBuffer.CopyToAsync(originalResponseStream);
    }
}