1.導出Excel：
頁面增加一個按鈕，單擊事件添加如下方法：
protected void Button1_Click(object sender, EventArgs e)
{
        Export("application/ms-excel", "學生成績報表.xls");
}private void Export(string FileType, string FileName)
{
        Response.Charset = "GB2312";
        Response.ContentEncoding = System.Text.Encoding.UTF7;
        Response.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(FileName, Encoding.UTF8).ToString());
        Response.ContentType = FileType;
        this.EnableViewState = false;
        StringWriter tw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(tw);
        GridView1.RenderControl(hw);
        Response.Write(tw.ToString());
        Response.End();
}
public override void VerifyRenderingInServerForm(Control control)
{
}

//如果沒有下面方法會報錯類型“GridView”的控件“GridView1”必須放在具有 runat=server 的窗體標記內
public override void VerifyRenderingInServerForm(Control control)
{
}

還有由于是文件操作所以要引入名稱空間IO和Text
2.讀取Excel：
private DataSet CreateDataSource()
{
        string strCon;
        strCon = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Server.MapPath("excel.xls") + "; Extended Properties=Excel 8.0;";
        OleDbConnection olecon = new OleDbConnection(strCon);
        OleDbDataAdapter myda = new OleDbDataAdapter("SELECT * FROM [Sheet1$]", strCon);
        DataSet myds = new DataSet();
        myda.Fill(myds);
        return myds;
}
protected void Button1_Click(object sender, EventArgs e)
{
        GridView1.DataSource = CreateDataSource();
        GridView1.DataBind();
}