只需将ContentType 设置为 "application/vnd.ms-excel",表示以Excel方式输出.
代码如下:
DataToExcel.aspx:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="DataToExcel.aspx.cs" Inherits="DataToExcel" %>

DataToExcel.aspx.cs
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;

public partial class DataToExcel : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!this.IsPostBack)
{
this.Response.ContentType = "application/vnd.ms-excel";
string ConnStr = "server=localhost;uid=sa;pwd=;database=northwind";
SqlConnection Conn = new SqlConnection(ConnStr);
Conn.Open();
string sqlcmd = "select lastname,firstname,title, address, city from employees";
SqlCommand cmd = new SqlCommand(sqlcmd, Conn);
SqlDataAdapter adapter = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
adapter.Fill(ds);
this.GridView1.DataSource = ds.Tables[0].DefaultView;
this.GridView1.DataBind();
}
}
}

来源:网络