asp.net-mvc - ASP.NET MVC 返回 Excel 文件

Question

我需要上传文件并修改然后返回相同的文件。我不需要将文件保存到任何位置，而是操作它并返回。但是我不知道如何返回文件。

下面的代码允许保存文件，我什至编写了不保存文件的代码。唯一的问题是我收到一个错误，表明该文件已被其他用户打开。

该进程无法访问文件“D:\Places\places\App_Data\877d36d3-ce29-48d1-995a-ea6652a528a7C2.xlsx”，因为该文件正在被另一个进程使用。

你能帮我吗

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult FileUpload(HttpPostedFileBase uploadFile)
{
    if (uploadFile.ContentLength > 0)
    {
        string path = string.Empty;
        var fileName = Path.GetFileName(uploadFile.FileName);
        path = Path.Combine(Server.MapPath("~/App_Data/"), Guid.NewGuid() + fileName);
        uploadFile.SaveAs(path);

        Excel.Application xlApp = new Excel.Application();
        Excel.Workbook xlWorkbook = xlApp.Workbooks.Open(path);
        Excel._Worksheet xlWorksheet = (Excel._Worksheet)xlWorkbook.Sheets[1];
        Excel.Range xlRange = xlWorksheet.UsedRange;
        int rowCount = xlRange.Rows.Count; int colCount = xlRange.Columns.Count;
        (xlRange.Cells[4, 5] as Excel.Range).Value2 = "asdF";
        (xlRange.Cells[4, 6] as Excel.Range).Value2 = "asdF";
        (xlRange.Cells[4, 7] as Excel.Range).Value2 = "asdF";
        (xlRange.Cells[4, 8] as Excel.Range).Value2 = "asdF";

        releaseObject(xlWorksheet);
        releaseObject(xlWorkbook);
        releaseObject(xlApp);
        GC.Collect();

        uploadFile.InputStream.Dispose();
        return File(path, "application/text");

    }
    else
    {
        return View();
    }
}

private void releaseObject(object obj)
{
    try
    {
        System.Runtime.InteropServices.Marshal.ReleaseComObject(obj);
        obj = null;
    }
    catch (Exception ex)
    {
        obj = null;
        //MessageBox.Show("Exception Occured while releasing object " + ex.ToString());
    }
    finally
    {enter code here
        GC.Collect();
    }
}

Answer 1

在操作中您可以返回 FileStreamResult

return new FileStreamResult([memory stream], "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");

您可能还想在返回之前关闭工作簿并将其保存到临时区域。从错误来看，文件似乎仍然打开。