C#将Sql数据保存到Excel文件中的方法

public string ExportExcel( DataSet ds,string saveFileName){  try  { if (ds == null)    return "数据库为空";  bool fileSaved = false; Microsoft.Office.Interop.Excel.Application xlApp = new Microsoft.Office.Interop.Excel.Application(); if (xlApp == null) {   return "无法创建Excel对象，可能您的机子未安装Excel"; } Microsoft.Office.Interop.Excel.Workbooks workbooks = xlApp.Workbooks; Microsoft.Office.Interop.Excel.Workbook workbook = workbooks.Add(Microsoft.Office.Interop.Excel.XlWBATemplate.xlWBATWorksheet); Microsoft.Office.Interop.Excel.Worksheet worksheet = (Microsoft.Office.Interop.Excel.Worksheet)workbook.Worksheets[1];//取得sheet1 //写入字段 for (int i = 0; i < ds.Tables[0].Columns.Count; i++) {   worksheet.Cells[1, i + 1] = ds.Tables[0].Columns[i].ColumnName; } //写入数值 for (int r = 0; r < ds.Tables[0].Rows.Count; r++) {   for (int i = 0; i < ds.Tables[0].Columns.Count; i++)   { worksheet.Cells[r + 2, i + 1] = ds.Tables[0].Rows[r][i];   }   System.Windows.Forms.Application.DoEvents(); } worksheet.Columns.EntireColumn.AutoFit();//列宽自适应。 if (saveFileName != "") {   try   { workbook.Saved = true; workbook.SaveCopyAs(saveFileName); fileSaved = true;   }   catch (Exception ex)   { fileSaved = false; MessageBox.Show("导出文件时出错,文件可能正被打开！/n" + ex.Message);   } } else {   fileSaved = false; } xlApp.Quit(); GC.Collect();//强行销毁 if (fileSaved && System.IO.File.Exists(saveFileName)) System.Diagnostics.Process.Start(saveFileName); //打开EXCEL return "成功保存到Excel";  }  catch (Exception ex)  { return ex.ToString();  }}