自动调整功能不格式化Excel中的单元格

Question

        Microsoft.Office.Interop.Excel.Application excel = new Microsoft.Office.Interop.Excel.Application();
        excel.Workbooks.Add();
        Microsoft.Office.Interop.Excel._Worksheet workSheet = excel.ActiveSheet;
        try
        {
            workSheet.Cells[1, "A"] = "Number #";
            workSheet.Cells[1, "B"] = "Firstname";
            workSheet.Cells[1, "C"] = "Lastname";
            workSheet.Cells[1, "D"] = "Email";
            workSheet.Cells[1, "E"] = "Mobile";
            // ------------------------------------------------
            // Populate sheet with some real data from list
            // ------------------------------------------------
            int row = 2; // start row (in row 1 are header cells)
            foreach (var hmn in humen)
            {
                workSheet.Cells[row, "A"] = hmn.Number;
                workSheet.Cells[row, "B"] = hmn.FirstName;
                workSheet.Cells[row, "C"] = hmn.LastName;
                workSheet.Cells[row, "D"] = hmn.Email;
                workSheet.Cells[row, "E"] = hmn.Mobile;
                row++;
            }

            workSheet.Range["A1", "E" + humen.Count].AutoFormat(Microsoft.Office.Interop.Excel.XlRangeAutoFormat.xlRangeAutoFormatClassic1);

            workSheet.Range["A2", "E" + humen.Count].EntireColumn.AutoFit();

            string fileName = string.Format(@"{0}\Resumes_{1}_Data{2}.xlsx", Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory), DateTime.Now.ToString("YYYY-MM-dd"), Guid.NewGuid().ToString().Substring(0, 4));

            workSheet.SaveAs(fileName);

为什么不起作用？具有正确的范围，仍然没有格式化单元格

 workSheet.Range["A2", "E" + humen.Count].EntireColumn.AutoFit();

不应该这样做吗？