如何在c#中编写内存流的单元测试？

嗨，我正在用c#编写单元测试。我正在编写使用openXML下载excel文件的单元测试。下面是我的单元测试

 [Fact]
      public void ShouldAddErrorColumnAtTheEnd()
      {
        var stream = new MemoryStream();
        var expectedHeaders = new[]
        {
          "Keycode",
          "Store",
          "Date On Range",
          "Date Off Range",
          "LSPL",
          "Active",
          "Ranged",
          "Errors",
        };
        var expectedRows = new[]
        {
          new string[] { "DEF", "1001",  "01/01/2100", "02/02/2100", "-1", "Y", "Y", "Oh no! Bad Lspl" }
        };

        var parameterUploadRepository = mockProvider.GetDependency<IParameterUploadRepository>();
        parameterUploadRepository.GetById(uploadId)
          .Returns(new ParameterUpload()
          {
            Type = Constants.ParameterUploadType.KeycodeParameterUpload,
            ID = uploadId,
          });

        var keycodeParameterChangesWithErrors = new List<KeycodeParameterChange>()
        {
          new KeycodeParameterChange()
          {
            UploadId = uploadId,
            Keycode = "DEF",
            Store = "1001",
            OnRange = "01/01/2100",
            OffRange = "02/02/2100",
            Lspl = "-1",
            Active = "Y",
            Ranged = "Y",
            Errors = "Oh no! Bad Lspl",
          }
        };
        parameterUploadRepository.GetKeycodeParameterChangesWithErrors(uploadId)
          .Returns(keycodeParameterChangesWithErrors);

        IEnumerable<string> actualHeaders = null;
        IEnumerable<IEnumerable<string>> actualRows = null;
        var excelService = mockProvider.GetDependency<IExcelWriterService>();
        excelService.WriteExcelUsingOpenXML(
            Arg.Do<IEnumerable<string>>(headers => actualHeaders = headers),
            Arg.Do<IEnumerable<IEnumerable<string>>>(rows => actualRows = rows),
            Constants.KeycodeParameterUpload.SheetName)
          .Returns(???);

        subject.GetUploadSyncErrors(uploadId);

        actualHeaders.ShouldBe(expectedHeaders);
        actualRows.ShouldBe(expectedRows);
      }

我不知道我该回去买什么

excelService.CreateExcelPackage(
            Arg.Do<IEnumerable<string>>(headers => actualHeaders = headers),
            Arg.Do<IEnumerable<IEnumerable<string>>>(rows => actualRows = rows),
            Constants.KeycodeParameterUpload.SheetName)
          .Returns(????);

excelService.CreateExcelPackage(
Arg.Do（headers=>actualHeaders=headers），
Arg.Do（行=>实际行=行），
Constants.KeycodeParameterUpload.SheetName）
.返回（？？）；

---

有人能帮我完成这个吗？任何帮助都将不胜感激。谢谢

您可以测试内存流的长度。如果失败，它将<1。如果需要，您还可以从内存流重新组装工作表。

您可以测试内存流的长度。如果失败，它将<1。如果需要，您还可以从内存流重新组装工作表

excelService.CreateExcelPackage(
            Arg.Do<IEnumerable<string>>(headers => actualHeaders = headers),
            Arg.Do<IEnumerable<IEnumerable<string>>>(rows => actualRows = rows),
            Constants.KeycodeParameterUpload.SheetName)
          .Returns(????);