引入  Microsoft.Office.Interop.Excel.dll
 格式：标题加了下划线，单元格内容居中
 1 using System;

 using System.Data;

 using System.Data.SqlClient;

 using System.Web.UI;    

      public static void DataSetToExcel(DataTable dataTable, string SaveFile)

             {

                 Microsoft.Office.Interop.Excel.Application excel;  

                 Microsoft.Office.Interop.Excel._Workbook workBook;  

                 Microsoft.Office.Interop.Excel._Worksheet workSheet;  

                 object misValue = System.Reflection.Missing.Value;  

                 excel = new Microsoft.Office.Interop.Excel.Application();

                 workBook = excel.Workbooks.Add(misValue);  

                 workSheet = (Microsoft.Office.Interop.Excel._Worksheet)workBook.ActiveSheet;  

                 int rowIndex = ;  

                 int colIndex = ;

                 //取得标题

                 foreach (DataColumn col in dataTable.Columns)

                 {

                     colIndex++;  

                     excel.Cells[, colIndex] = col.ColumnName;

                     Microsoft.Office.Interop.Excel.Range range = workSheet.Range[workSheet.Cells[, colIndex],workSheet.Cells[,colIndex]];

                     range.Font.Underline = true;

                 }

                 //取得表格中的数据

                 foreach (DataRow row in dataTable.Rows)

                 {

                     rowIndex++;  

                     colIndex = ;  

                     foreach (DataColumn col in dataTable.Columns)

                     {

                        colIndex++;  

                        excel.Cells[rowIndex, colIndex] =   

                             row[col.ColumnName].ToString().Trim();

                        Microsoft.Office.Interop.Excel.Range range = workSheet.Range[excel.Cells[rowIndex, colIndex], excel.Cells[rowIndex, colIndex]];

                        range.HorizontalAlignment = Microsoft.Office.Interop.Excel.XlVAlign.xlVAlignCenter;

                     }

                 }  

                 excel.Visible = false;

                 excel.DisplayAlerts = false;

                 if (workSheet != null)

                 {

                     workBook.SaveAs(SaveFile, Microsoft.Office.Interop.Excel.XlFileFormat.xlWorkbookNormal, misValue,

                         misValue, misValue, misValue, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlExclusive,

                         misValue, misValue, misValue, misValue, misValue);

                 }

                 dataTable = null;  

                 workBook.Close(true, misValue, misValue);  

                 excel.Quit();  

                 releaseObject(workSheet);  

                 releaseObject(workBook);  

                 releaseObject(excel);  

             }  

             private static void releaseObject(object obj)

             {

                 try

                 {

                     System.Runtime.InteropServices.Marshal.ReleaseComObject(obj);

                     obj = null;

                 }

                 catch

                 {

                     obj = null;

                 }

                 finally

                 {

                     GC.Collect();

                 }

             }

  DataSetToExcel(ds.Tables[], @"D:\ZhaoNick\Desktop\test.xls");