asp.net 动态添加控件

    protected void Page_Load(object sender, EventArgs e)
    {
        Control c = this.ParseControl(" <asp:Button ID='Button1' runat='server' Text='Button' CommandArgument = 'b1' />");
        PlaceHolder1.Controls.Add(c);
        Button b = (Button)FindControl("Button1");
        b.Command += new CommandEventHandler(b_Command);
    }

    void b_Command(object sender, CommandEventArgs e)
    {
        switch (e.CommandArgument.ToString())
        {
            case "b1":

                break;
        }
    }