动态生成用户控件时窗体标记runat服务器的问题

Question

我试图动态生成一个用户控件，它由标签、下拉菜单和文本框组成，这样我就可以设置标签的值。当我运行它时，我遇到了一个关于下拉菜单和文本框的问题，因为它们需要在runat服务器的表单标记中。当我添加表单标记时，编译器抱怨只能有一个表单标记。请帮忙。这是我的代码：

用户控件：

 <%@ Control Language="C#" AutoEventWireup="true"
    CodeFile="IngredientQuantityControl.ascx.cs" Inherits="IngredientQuantityControl" %>
<asp:Label ID="IngredientDisplay" runat="server" Text="Label"></asp:Label>

<asp:DropDownList ID="DropDownList1" runat="server" >
    <asp:ListItem Value=null >Please Choose a Unit</asp:ListItem>
    <asp:ListItem Value="Unit">Unit(s)</asp:ListItem>
    <asp:ListItem>Cup</asp:ListItem>
    <asp:ListItem>Tbsp</asp:ListItem>
   <asp:ListItem>Tsp</asp:ListItem>
    <asp:ListItem>To Taste</asp:ListItem>
    <asp:ListItem>Milligrams</asp:ListItem>
</asp:DropDownList>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>

    using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class IngredientQuantityControl : System.Web.UI.UserControl
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    public void SetLabelText(String s)
    {
        IngredientDisplay.Text = s;
    }


}

 protected void Button1_Click(object sender, EventArgs e)
    {
       Page.Controls.Add(LoadControl("IngredientQuantityControl.ascx"));

        IngredientQuantityControl uc = (IngredientQuantityControl)Page.LoadControl("IngredientQuantityControl.ascx");
        uc.SetLabelText("Halleluyah!");

        Panel1.Controls.Add(uc);

        //string text = listBox1.GetItemText(listBox1.SelectedItem);
    }
}

Answer 1

您将CompriguentQuantityControl.ascx作为控件添加了两次。

  protected void Button1_Click(object sender, EventArgs e)
    {
        IngredientQuantityControl uc = (IngredientQuantityControl)Page.LoadControl("IngredientQuantityControl.ascx");
        uc.SetLabelText("Halleluyah!");
        Panel1.Controls.Add(uc);
        //string text = listBox1.GetItemText(listBox1.SelectedItem);
    }