如何使用占位符？

Question

我的页面上有一个占位符，似乎无法让它做一个简单的超链接。当然我错过了什么？这是代码：

word.aspx

<asp:PlaceHolder ID="PlaceHolder1" runat="server">
    <asp:HyperLink ID="Link1" runat="server" />
</asp:PlaceHolder>

或

<asp:PlaceHolder ID="PlaceHolder1" runat="server">
</asp:PlaceHolder>

和背后的代码：

Imports System.Collections.Generic
Imports System.Linq
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts

Partial Public Class Word
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(sender As Object, e As EventArgs)
        Dim hyperlink1 As New HyperLink()
        hyperlink1.Text = "Devmanuals"
        hyperlink1.NavigateUrl = "http://www.devmanuals.com/"
        PlaceHolder1.Controls.AddAt(0, hyperlink1)
    End Sub
End Class

或

Imports System.Collections.Generic
Imports System.Linq
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts

Partial Public Class Word
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(sender As Object, e As EventArgs)
        Dim hyperlink1 As New HyperLink()
        hyperlink1.Text = "Devmanuals"
        hyperlink1.NavigateUrl = "http://www.devmanuals.com/"
        PlaceHolder1.Controls.Add(hyperlink1)
    End Sub
End Class

我没办法上班。