****************************Demo.aspx

   <form id="form1" runat="server">
    <div>
   
        <asp:DataList ID="DataList1" runat="server"
            oneditcommand="DataList1_EditCommand" onitemcommand="DataList1_ItemCommand"
            onupdatecommand="DataList1_UpdateCommand"
            ondeletecommand="DataList1_DeleteCommand">
            <EditItemTemplate>
                <table style="width:100%;">
                    <tr>
                        <td class="style1">
                            姓名</td>
                        <td>
                            <asp:TextBox ID="txtname" runat="server" Text='<%# Eval("sname") %>'></asp:TextBox>
                        </td>
                    </tr>
                    <tr>
                        <td class="style1">
                            性別</td>
                        <td>
                            <asp:TextBox ID="txtsex" runat="server" Text='<%# Eval("sex") %>'></asp:TextBox>
                        </td>
                    </tr>
                    <tr>
                        <td class="style1">
                            年齡</td>
                        <td>
                            <asp:TextBox ID="txtage" runat="server" Text='<%# Eval("age") %>'></asp:TextBox>
                        </td>
                    </tr>
                    <tr>
                        <td class="style1">
                            <asp:Button ID="update" runat="server" CommandArgument='<%# Eval("sid") %>'
                                CommandName="update" Text="更新" Width="40px" />
                        </td>
                        <td>
                            <asp:Button ID="Bucancel" runat="server" CommandName="cancel" Text="取消" />
                        </td>
                    </tr>
                </table>
            </EditItemTemplate>
            <ItemTemplate>
                姓名:<asp:Label ID="Label1" runat="server" Text='<%# Eval("sname") %>'></asp:Label>
                <br />
                <br />
                年齡:<asp:Label ID="Label2" runat="server" Text='<%# Eval("age") %>'></asp:Label>
                <br />
                <br />
                性別:<asp:Label ID="Label3" runat="server" Text='<%# Eval("sex") %>'></asp:Label>
                <br />
                <br />
                <asp:Button ID="btnedit" runat="server" CommandName="edit" Height="21px"
                    Text="編輯" />
                &nbsp;<asp:Button ID="btndelete" runat="server" CommandArgument='<%# Eval("sid") %>'
                    CommandName="delete" Text="刪除" />
                <br />
                <br />
                <asp:Button ID="Button1" runat="server" CommandArgument='<%# Eval("sid") %>'
                    CommandName="buy" Text="加入購物車" />
                <br />
            </ItemTemplate>
        </asp:DataList>
   
    </div>
    </form>

*****************************

****************************Demo.aspx.cs

namespace DataList
{
    public partial class Demo : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if(!IsPostBack )
            {
               bindData();
            }
        }

        private void bindData()
        {
            string sql = "select * from student";
            DataTable dt = sqlhelp.Executedatatable(sql);
            this.DataList1.DataSource = dt;
            this.DataList1.DataBind();
        }

        protected void DataList1_ItemCommand(object source, DataListCommandEventArgs e)
        {
            if (e.CommandName == "buy")
            {
                Response.Write(e.CommandArgument .ToString ());
            }

        }

        protected void DataList1_EditCommand(object source, DataListCommandEventArgs e)
        {
            this.DataList1.EditItemIndex = e.Item.ItemIndex;
            this.bindData();//重新在綁一次

        }

        protected void DataList1_UpdateCommand(object source, DataListCommandEventArgs e)
        {
            string name = (e.Item.FindControl("txtname") as TextBox).Text;
            string sex = (e.Item.FindControl("txtsex") as TextBox).Text;
            string age = (e.Item.FindControl("txtage") as TextBox).Text;
            string sql = "update student set [email protected],[email protected],[email protected] where [email protected]";
            SqlParameter[] pms = new SqlParameter[]
           {
               new SqlParameter ("@name",name ),
               new SqlParameter ("@sex",sex ),
               new SqlParameter ("@age",age ),
               new SqlParameter ("@sid",e.CommandArgument )
            
           };
            sqlhelp.ExcuteNonQuery(sql,pms);
        }

        protected void DataList1_CancelCommand(object source, DataListCommandEventArgs e)
        {
            this.DataList1.EditItemIndex = -1;//誰也不編輯了
            this.bindData();//再重新繫結一下
        }

        protected void DataList1_DeleteCommand(object source, DataListCommandEventArgs e)
        {
            string sql = "delete from student where [email protected]" ;
            SqlParameter pm = new SqlParameter("@sid",e.CommandArgument );
            sqlhelp.ExcuteNonQuery(sql,pm);
            this.bindData();
        }