带有内容模板的ASP.NET自定义控件

时间:2012-09-27 09:56:41

标签: c# asp.net user-controls custom-controls

我在ASP.NET 3.5中创建了LoginView ASP.NET控件的“克隆”,以满足我们公司的需求,并且我试图了解它是如何实现在不同模板中设置具有相同ID的控件的能力的。 例如,这是使用LoginView控件的ASPX标记:

    <asp:LoginView ID="lv" runat="server">
        <AnonymousTemplate>
            <asp:Label ID="lbl" runat="server" />
        </AnonymousTemplate>
        <LoggedInTemplate>
            <asp:Label ID="lbl" runat="server" />
        </LoggedInTemplate>
    </asp:LoginView>

这是有效的标记,页面工作正常 现在我创建了自定义控件:

    [ParseChildren(true)]
    [PersistChildren(false)]
    public class ContentControl : Panel
    {
        [PersistenceMode(PersistenceMode.InnerProperty)]
        public PlaceHolder AnonymousView { get; set; }

        [PersistenceMode(PersistenceMode.InnerProperty)]
        public PlaceHolder LoggedinView { get; set; }

        public ContentControl()
        {
            this.Init += new EventHandler(ContentControl_Init);
        }

        void ContentControl_Init(object sender, EventArgs e)
        {
            if (AnonymousView == null)
            {
                AnonymousView = new PlaceHolder();
            }

            if (LoggedinView == null)
            {
                LoggedinView = new PlaceHolder();
            }

            this.Controls.Add(AnonymousView);
            this.Controls.Add(LoggedinView);

            AnonymousView.ID = "AnonymousView";
            LoggedinView.ID = "LoggedinView";

            AnonymousView.Visible = !MyContext.IsLogged;
            LoggedinView.Visible = MyContext.IsLogged;
        }
    }

现在当我使用我的控件和以下标记时,我收到错误,即ID为“lbl”的控件在页面上存在多次:

    <TL:ContentControl ID="c" runat="server" CssClass="dd">
        <AnonymousView>
            AnonymousView
            <asp:Label ID="lbl" runat="server" />
        </AnonymousView>
        <LoggedinView>
            LoggedinView
            <asp:Label ID="lbl" runat="server" />
        </LoggedinView>
    </TL:ContentControl>

如何允许两个模板中具有相同ID的控件?

1 个答案:

答案 0 :(得分:3)

您需要开发模板化控件:Building Templated Custom ASP.NET Server Controls

并使用实现INamingContainer的控件作为模板容器:Use TemplateInstance.Single to avoid FindControls