C#导出到Excel模板中,保存后Excel进程无法结束
int rowCount = dt.Rows.Count; //源DataTable行数
  int colCount = (dt.Columns.Count - 9); //源DataTable列数减一，最后一列为项目类型名称，用于标题的
  int sheetCount = this.GetSheetCount(rowCount, rows); //WorkSheet个数，即页数
  DateTime beforeTime;
  DateTime afterTime;

  if (sheetPrefixName == null || sheetPrefixName.Trim() == "")
  sheetPrefixName = "Sheet";

  //创建一个Application对象并使其可见
  beforeTime = DateTime.Now;
  Excel.Application app = new Excel.ApplicationClass();
  app.Visible = true;
  afterTime = DateTime.Now;

  //打开模板文件，得到WorkBook对象
  Excel.Workbook workBook = app.Workbooks._Open(templetFile, missing, missing, missing, missing, missing,
  missing, missing, missing, missing, missing, missing, missing);
   
  //得到一个WorkSheet对象
  Excel.Worksheet workSheet = (Excel.Worksheet)workBook.Sheets.get_Item(1);

  //复制sheetCount-1个WorkSheet对象
  for (int i = 1; i < sheetCount; i++)
  {
  ((Excel.Worksheet)workBook.Worksheets.get_Item(i)).Copy(missing, workBook.Worksheets[i]);
  }

  //将源DataTable数据写入Excel
  for (int i = 1; i <= sheetCount; i++)
  {
  int startRow = (i - 1) * rows; //记录起始行索引
  int endRow = i * rows; //记录结束行索引

  //若是最后一个WorkSheet，那么记录结束行索引为源DataTable行数
  if (i == sheetCount)
  endRow = rowCount;

  //获取要写入数据的WorkSheet对象，并重命名
  Excel.Worksheet sheet = (Excel.Worksheet)workBook.Worksheets.get_Item(i);
  sheet.Name = sheetPrefixName + "-" + i.ToString();

  //将dt中的数据写入WorkSheet
  for (int j = 0; j < endRow - startRow; j++)
  {
  int z = startRow + j + 1;
  sheet.Cells[top + j, left] = z.ToString();//第一列为检索结果的序号
  for (int k = 1; k < colCount + 1; k++)
  {
  sheet.Cells[top + j, left + k] = dt.Rows[startRow + j][k].ToString();
  }
  }

  }
  //输出Excel文件并退出
  try
  {
  workBook.SaveAs(outputFile, missing, missing, missing, missing, missing, Excel.XlSaveAsAccessMode.xlExclusive, missing, missing, missing, missing, missing);
  workBook.Close(null, null, null);
  app.Workbooks.Close();
  app.Application.Quit();
  app.Quit();
  }
  catch (Exception e)
  {
  throw e;
  }
  finally
  {
  System.Runtime.InteropServices.Marshal.ReleaseComObject(workSheet);
  System.Runtime.InteropServices.Marshal.ReleaseComObject(workBook);
  System.Runtime.InteropServices.Marshal.ReleaseComObject(app);

  workSheet = null;
  workBook = null;
  app = null;

  GC.Collect();
  }