导出EXCEL的问题。
能不能将Grid导出到EXCEL的数据透视表

------解决方案--------------------
用Excel的宏记录一下过程
然后把宏生成的代码放到你的代码里执行即可
------解决方案--------------------
http://www.cnblogs.com/lovecherry/archive/2005/03/25/125519.html

看看这个
------解决方案--------------------
using System;
using System.IO;
using Excel;

namespace Openet.Utility.ExcelTools
{
/// <summary>
/// ExcelOption 的摘要说明。
/// </summary>
public class ExcelTools
{
public ExcelTools()
{

}

/// <summary>
/// 导出到EXCEL表
/// </summary>
public static void toExcel(string FileName, string SheetName, System.Data.DataTable dt)
{
Excel.ApplicationClass myExcel = new Excel.ApplicationClass();
Excel.Worksheet worksheet = null;

string curPath = Directory.GetParent(FileName).FullName;
if(!Directory.Exists(curPath))
{
Directory.CreateDirectory(curPath);
}

if (File.Exists(FileName))
{
try
{
File.Delete(FileName);
}
catch
{
throw new Exception( "文件操作出错，可能正在运行当前的EXCEL文件！ ");
}
}

try
{
object missing = System.Reflection.Missing.Value;

myExcel.Workbooks.Add(missing);
worksheet = (Excel.Worksheet)myExcel.ActiveSheet;
worksheet.Name = SheetName;
myExcel.Visible = false;


int iRows = dt.Rows.Count;
int iCol = dt.Columns.Count;

worksheet.get_Range( worksheet.Cells[1, 1], worksheet.Cells[ iRows+1, iCol] ).NumberFormatLocal = "@ ";

for( int i=0; i <iCol; i++)
{
worksheet.Cells[1,i+1] = dt.Columns[i].ToString();
}

int size = iRows / 1000;
int page = 0;
string[,] rows = null;
for(int i=0; i <iRows; )
{
if(page <size)
{
rows = new string[1000,iCol];
for(int count=0;count <1000;count++)
{
for(int j=0; j <iCol; j++)
{
rows[count,j] = dt.DefaultView[i][j].ToString();
}
i++;
}
worksheet.get_Range(worksheet.Cells[page * 1000 + 2, 1], worksheet.Cells[ page * 1000 + 1001, iCol]).Value2 = rows;
page++;
}
else
{
int left = iRows % 1000;
rows = new string[left,iCol];
for(int count=0;count <left;count++)
{
for(int j=0; j <iCol; j++)
{
rows[count,j] = dt.DefaultView[i][j].ToString();
}
i++;
}
worksheet.get_Range(worksheet.Cells[iRows+2-left, 1], worksheet.Cells[ iRows+1, iCol]).Value2 = rows;
}
}

worksheet.SaveAs( FileName, missing, missing, missing, missing, missing, missing, missing, missing, missing);

}
catch(Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
myExcel.Workbooks.Close();
myExcel.Quit();

System.Runtime.InteropServices.Marshal.ReleaseComObject(worksheet);
System.Runtime.InteropServices.Marshal.ReleaseComObject(myExcel);
worksheet = null;
myExcel = null;
GC.Collect();
}

}

/// <summary>
/// 因为调用EXCEL后，结束时EXCEL进程并没有立即KILL，用这个方法调用可以KILL掉EXCEL