1、由dataset生成

public void CreateExcel(DataSet ds,string typeid,string FileName)
{
HttpResponse resp;
resp = Page.Response;
resp.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
resp.AppendHeader("Content-Disposition", "attachment;filename=" + FileName);
string colHeaders= "", ls_item="";
int i=0;

//定义表对象与行对像，同时用DataSet对其值进行初始化
DataTable dt=ds.Tables[0];
DataRow[] myRow=dt.Select("");
// typeid=="1"时导出为EXCEL格式文件；typeid=="2"时导出为XML格式文件
if(typeid=="1")
{
//取得数据表各列标题，各标题之间以\t分割，最后一个列标题后加回车符
for(i=0;i colHeaders+=dt.Columns[i].Caption.ToString()+"\t";
colHeaders +=dt.Columns[i].Caption.ToString() +"\n";
//向HTTP输出流中写入取得的数据信息
resp.Write(colHeaders);
//逐行处理数据
foreach(DataRow row in myRow)
{
//在当前行中，逐列获得数据，数据之间以\t分割，结束时加回车符\n
for(i=0;i ls_item +=row[i].ToString() + "\t";
ls_item += row[i].ToString() +"\n";
//当前行数据写入HTTP输出流，并且置空ls_item以便下行数据
resp.Write(ls_item);
ls_item="";
}
}
else
{
if(typeid=="2")
{
//从DataSet中直接导出XML数据并且写到HTTP输出流中
resp.Write(ds.GetXml());
}
}
//写缓冲区中的数据到HTTP头文件中
resp.End();


}



2、使用微软的C＋＋写的ACTIVEX控件：http://download.microsoft.com/download/OfficeXPDev/sample/1.0/WIN98MeXP/EN-US/Dsoframerctl.exe
3、由datagrid生成：

public void ToExcel(System.Web.UI.Control ctl)
{
HttpContext.Current.Response.AppendHeader("Content-Disposition","attachment;filename=Excel.xls");
HttpContext.Current.Response.Charset ="UTF-8";
HttpContext.Current.Response.ContentEncoding =System.Text.Encoding.Default;
HttpContext.Current.Response.ContentType ="application/ms-excel";//image/JPEG;text/HTML;image/GIF;vnd.ms-excel/msword
ctl.Page.EnableViewState =false;
System.IO.StringWriter tw = new System.IO.StringWriter() ;
System.Web.UI.HtmlTextWriter hw = new System.Web.UI.HtmlTextWriter (tw);
ctl.RenderControl(hw);
HttpContext.Current.Response.Write(tw.ToString());
HttpContext.Current.Response.End();
}

用法：ToExcel(datagrid1);


4、这个用dataview ，代码好长

public void OutputExcel(DataView dv,string str)
{
//
// TODO: 在此处添加构造函数逻辑
//
//dv为要输出到Excel的数据，str为标题名称
GC.Collect();
Application excel;// = new Application();
int rowIndex=4;
int colIndex=1;

_Workbook xBk;
_Worksheet xSt;

excel= new ApplicationClass();

xBk = excel.Workbooks.Add(true);

xSt = (_Worksheet)xBk.ActiveSheet;

//
//取得标题
//
foreach(DataColumn col in dv.Table.Columns)
{
colIndex++;
excel.Cells[4,colIndex] = col.ColumnName;
xSt.get_Range(excel.Cells[4,colIndex],excel.Cells[4,colIndex]).HorizontalAlignment = XlVAlign.xlVAlignCenter;//设置标题格式为居中对齐
}

//
//取得表格中的数据
//
foreach(DataRowView row in dv)
{
rowIndex ++;
colIndex = 1;
foreach(DataColumn col in dv.Table.Columns)
{
colIndex ++;
if(col.DataType == System.Type.GetType("System.DateTime"))
{
excel.Cells[rowIndex,colIndex] = (Convert.ToDateTime(row[col.ColumnName].ToString())).ToString("yyyy-MM-dd");
xSt.get_Range(excel.Cells[rowIndex,colIndex],excel.Cells[rowIndex,colIndex]).HorizontalAlignment = XlVAlign.xlVAlignCenter;//设置日期型的字段格式为居中对齐
}
else
if(col.DataType == Sys