CsvHelper对象引用未设置为对象的实例(GetRecords问题)

我在跟踪 this example . 据我所知 GetRecords 当我向 GetHist 终点,但我不明白为什么。

我查过了:

1. 我的数据遵循c#类的精确命名约定(我从csv中复制了名称,以在c#中创建变量名)
2. 文件输入路径正确。
3. 即时消息使用最新版本的CsvHelper(12.1.0)

GetData调用的堆栈跟踪:

“”位于CsvHelper.CsvReader.GetRecordsT+MoveNext()\r\n位于System.Collections.Generic.LargeArrayBuilder 1.AddRange(IEnumerable 在System.Collections.Generic.EnumerableHolpers.ToArray[T](IEnumerable)上的1项 1 source)\r\n at System.Linq.Enumerable.ToArray[TSource](IEnumerable 1源文件\r\n位于System.Linq.SystemCore_EnumerableDebugView`1.get_Items()“

我的代码:

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using CsvHelper;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Mvc;

public class DataController : Controller
{

    private readonly IHostingEnvironment _hostingEnvironment;

    public DataController(IHostingEnvironment hostingEnvironment)
    {
        _hostingEnvironment = hostingEnvironment;
    }

    [HttpGet("[action]")]
    public IEnumerable<OHLCData> GetHist()
    {
        var v=OHLCData.GetData(_hostingEnvironment);
        return v;
    }

    public class OHLCData
    {
        string time;
        double oask, hask, lask, cask, obid, hbid, lbid, cbid;
        int volume;

        //@TODO: shouldnt pass it to this class from controller, should set in startup and read in this method
        public static IEnumerable<OHLCData> GetData(IHostingEnvironment _hostingEnvironment)
        {
            string filepath = Path.Combine(_hostingEnvironment.WebRootPath, "EUR_USD.csv");
            using (var reader = new StreamReader(filepath))
            using (var csv = new CsvReader(reader))
            {
                return csv.GetRecords<OHLCData>();
            }
        }
    }
}