求教Panel动态添加控件问题

Question

现在有一个panel,panel外面有个button,当我点击button的时候在panel里面加1个textbox,2个button.而且无刷新(用了ajax).
但是出了一个问题,当我点第2次以后 添加的时候panel里面始终只显示3个控件(1个textbox,2个button)求教如何解决.
代码如下:
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
                        <ContentTemplate>
                            <asp:Label ID="lblMessage" runat="server" ForeColor="Red" Text="lblMessage" 
                                Visible="False"></asp:Label>
                            <asp:RadioButtonList ID="rblNums" runat="server" RepeatDirection="Horizontal" 
                                Visible="False" RepeatColumns="5">
                            </asp:RadioButtonList>
                            <asp:Button ID="btnAdd" runat="server" Text="添加一帧" onclick="btnAdd_Click" />
                            <asp:Button ID="btnDelete" runat="server" Text="删除最后一帧" onclick="btnDelete_Click" />
                            <asp:Panel ID="panelContent" runat="server"></asp:Panel>                        </ContentTemplate>
                        <Triggers>
                            <asp:AsyncPostBackTrigger ControlID="btnAdd" EventName="Click" />
                            <asp:AsyncPostBackTrigger ControlID="btnDelete" EventName="Click" />
                            <asp:AsyncPostBackTrigger ControlID="btnSave" EventName="Click" />                        </Triggers>
                    </asp:UpdatePanel>
                    <asp:Button ID="btnSave" runat="server" Text="保存" onclick="btnSave_Click" />  
后台代码:                        System.Web.UI.WebControls.TextBox txtShowContent = new TextBox();                        txtShowContent.Width = 150;
                        txtShowContent.Height = 200;
                        txtShowContent.TextMode = TextBoxMode.MultiLine;                        NewButton newbtnModify = new NewButton();                        newbtnModify.Text = "修改";
                        newbtnModify.DeleteOrModifyAddress = address;                        NewButton newbtnDelete = new NewButton();                        newbtnDelete.Text = "删除";
                        newbtnDelete.DeleteOrModifyAddress = address;
                        this.panelContent.Controls.Add(txtShowContent);
                        this.panelContent.Controls.Add(newbtnModify);
                        this.panelContent.Controls.Add(newbtnDelete);
                        this.panelContent.Visible = true;                  

Answer 1

你这个，你把控件加到Panel上时就已经确定了这个控件的唯一性，当你再次单击按钮还能再接着添加吗？
不行吧，你动态生成的控件在浏览器端应该也是唯一的了！怎么可能再接着加呢，它的ID，你加到Panel中时已经默认会给了吧

Answer 2

int a = 0;
                        System.Web.UI.WebControls.TextBox txtShowContent = new TextBox();
                        txtShowContent.ID = a.ToString();
                        txtShowContent.Width = 150;
                        txtShowContent.Height = 200;
                        txtShowContent.TextMode = TextBoxMode.MultiLine;                        NewButton newbtnModify = new NewButton();
                        newbtnModify.ID = a.ToString();
                        newbtnModify.Text = "修改";
                        newbtnModify.DeleteOrModifyAddress = address;                        NewButton newbtnDelete = new NewButton();
                        newbtnDelete.ID = (a + 1).ToString();
                        newbtnDelete.Text = "删除";
                        
                        newbtnDelete.DeleteOrModifyAddress = address;                        
                        
                        this.panelContent.Controls.Add(txtShowContent);
                        this.panelContent.Controls.Add(newbtnModify);
                        this.panelContent.Controls.Add(newbtnDelete);
                        this.panelContent.Visible = true;
                        a++;
                        ViewState["newbtnModify"] = true;
                        ViewState["newBtnDelete"] = true;
                        ViewState["txtShowContent"] = true;
设置了ID 还是不得行

Answer 3

不是这个意思！！你这样改，不还是那些控件吗，无非是显式的加上了，你可以再拖入一个Panel，将上面动态生成的也加入这个Panel中，再看看加上没有

Answer 4

panel里面加panel 我也试过了 还是不行

Answer 5

根本就没加上去吧，
你点击两下后，还是那第一次加上的控件
你Form.Contorls.Count
总共还是那些个控件数目吧
怎么加呢？啊啊啊 我也晕了，怎么没高手来

Answer 6

没有做过无刷新的，但做过有刷新的点击button动态添加控件，添加之后，再次页面刷新时，页面控件就消失了
你的总是显示3个，可能就是这个原因
建议：将添加过的控件存起来，比如存在ViewState或Session中
再点button添加时，先从Session中读出以前添加过的，然后在页面上添加一次，最后再添加这次要“新”添加的//希望对你有帮助

Answer 7

好的 谢谢你,我去试试 
我在单独的一个页面里这样试过 private static Panel p = new Panel();
    protected void Page_Load(object sender, EventArgs e)
    {
        this.Controls.Add(p);
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        Label label = new Label();
        label.Text = "ccc";
        this.Panel1.Controls.Add(label);
    }这样的话就能 加进去  现在还在试 Ajax无刷新添加.但未能成功,继续加油...

Answer 8

protected void Button1_Click(object sender, EventArgs e)
  {
  Label label = new Label();
  label.Text = "ccc";
  p.Controls.Add(label);
  }

Answer 9

public partial class asp_DynamicControls : System.Web.UI.Page
{
    public int Quantity
    {
        get
        {
            return ViewState["Quantity"] != null ? (int)ViewState["Quantity"] : 1;
        }
        set { ViewState["Quantity"] = value; }
    }
    protected void Page_Load(object sender, EventArgs e)
    {
      
    }
    protected void btnSave_Click(object sender, EventArgs e)
    {  
     int nCount=Quantity;
     string strTxt = this.Request["txt"]!=null?this.Request["txt"].ToString():"";
     string[] arrTxt = strTxt.Split(',');
    List<string> lstAddItem = getItem(this.panelContent);
    for (int i = 1; i <= nCount; i++)
    {
            System.Web.UI.WebControls.TextBox txtShowContent = new TextBox();
            txtShowContent.Width = 150;
            txtShowContent.Height = 200;
            txtShowContent.TextMode = TextBoxMode.MultiLine;
            txtShowContent.ID = "txt";
            Button newbtnModify = new Button();
            newbtnModify.Text = "修改";
            Button newbtnDelete = new Button();
            newbtnDelete.Text = "删除";
            this.panelContent.Controls.Add(txtShowContent);
            this.panelContent.Controls.Add(newbtnModify);
            this.panelContent.Controls.Add(newbtnDelete);
            this.panelContent.Visible = true;
         if (i < nCount)
         {
             if (this.Request["txt"] != null&&arrTxt.Length>i-1)
             {
                 txtShowContent.Text = arrTxt[i-1];
             }
        }    
        if (i == nCount)
        {
            ViewState["Quantity"] = nCount + 1;
        }
    }
        
    }    #region 获得Panel值(TextBox)(未使用)
    /// <summary>
    /// 获得Panel值(TextBox)
    /// </summary>
    /// <param name="dl"></param>
    /// <returns></returns>
    private List<string> getItem(Panel pl)
    {        List<string> lstAddItem = new List<string>();
        try
        {
            int nPlCount = pl.Controls.Count;
            for (int i = 0; i < nPlCount; i++)
            {
                Object obj = (Object)pl.Controls[i];
                if (obj is TextBox)
                {
                    TextBox txt1 = (TextBox)obj;
                    lstAddItem.Add(txt1.Text.Trim());
                    continue;
                }
            }
        }
        catch (Exception ex)
        {
        }
        return lstAddItem;
    }
    #endregion
}
这个是后台程序 看看能不能解决你的问题