Question

拥有母版页。内容页面有一个列表，其中包含包含请求变量的超链接。您单击其中一个链接转到包含radiobuttonlist（可能）的页面。

第一个问题：当我到达新页面时，我使用其中一个变量来确定是否将radiobuttonlist添加到页面上的占位符。我尝试在页面中执行此操作_load但是无法获取所选的值。当我在preInit中玩这个时，第一次页面就在那里，我无法进入页面的控件。（对象引用未设置为对象的实例。）我认为它与MasterPage和页面内容有关？控件直到稍后才会实例化？（顺便使用vb）

第二个问题：说我开始工作，一旦我点击按钮，我是否仍然可以访问传递的请求变量以确定radiobuttonlist中的所选项目？

    Protected Sub Page_PreInit(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.PreInit
    'get sessions for concurrent 

    Dim Master As New MasterPage
    Master = Me.Master

    Dim myContent As ContentPlaceHolder = CType(Page.Master.FindControl("ContentPlaceHolder1"), ContentPlaceHolder)
    If Request("str") = "1" Then
        Dim myList As dsSql = New dsSql()   ''''instantiate the function to get dataset
        Dim ds As New Data.DataSet

        ds = myList.dsConSessionTimes(Request("eid"))
        If ds.Tables("conSessionTimes").Rows.Count > 0 Then
            Dim conY As Integer = 1

            CType(myContent.FindControl("lblSidCount"), Label).Text = ds.Tables("conSessionTimes").Rows.Count.ToString

很抱歉这么有需要 - 但也许有人可以指导我到一个带例子的页面？也许看到它会有所帮助吗？

感谢.... JB

Answer 1

如果您有内容占位符，是否可以将单选按钮列表控件添加到那里？

在母版页上：

<asp:ContentPlaceHolder id="ContentPlaceHolderForRadioButtonList" runat="server">       
</asp:ContentPlaceHolder>

一些链接，包含下一页使用的请求变量。

<a href="RadioButtonList.aspx?ref=first" >Link 1</a>
<a href="RadioButtonList.aspx?ref=second" >Link 2</a><br />
<a href="RadioButtonList.aspx?ref=third" >Link 3</a><br />
<a href="RadioButtonList.aspx?ref=forth" >Link 4</a><br />
<a href="RadioButtonList.aspx?ref=fifth" >Link 5</a><br />
<a href="RadioButtonList.aspx?ref=sixth" >Link 6</a>

现在在带有单选按钮列表的页面上，将其添加到内容占位符中。

<asp:Content ID="Content3" ContentPlaceHolderID="ContentPlaceHolderForRadioButtonList" Runat="Server">
<!-- radio button list to be dynamically populated-->
    <asp:RadioButtonList ID="RadioButtonList1" runat="server">
    </asp:RadioButtonList>
</asp:Content>

RadioButtonList.aspx：用于根据传入的信息动态填充单选按钮列表的代码。

 Partial Class RadioButtonList
    Inherits System.Web.UI.Page
    Private selection As String = ""

    Protected Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
        selection = IIf(Request.QueryString("ref") IsNot Nothing, Request.QueryString("ref"), "")
        If selection = "first" Then
            RadioButtonList1.Items.Add(New ListItem("first", "1"))
            RadioButtonList1.Items.Add(New ListItem("third", "3"))
            RadioButtonList1.Items.Add(New ListItem("fifth", "5"))
        ElseIf selection = "second" Then
            RadioButtonList1.Items.Add(New ListItem("second", "2"))
            RadioButtonList1.Items.Add(New ListItem("forth", "4"))
            RadioButtonList1.Items.Add(New ListItem("sixth", "6"))
        Else
            RadioButtonList1.Items.Add(New ListItem("first", "1"))
            RadioButtonList1.Items.Add(New ListItem("second", "2"))
            RadioButtonList1.Items.Add(New ListItem("third", "3"))
            RadioButtonList1.Items.Add(New ListItem("forth", "4"))
            RadioButtonList1.Items.Add(New ListItem("fifth", "5"))
            RadioButtonList1.Items.Add(New ListItem("sixth", "6"))
        End If

        'set the selected radio button
        For i As Integer = 0 To RadioButtonList1.Items.Count - 1
            If RadioButtonList1.Items(i).Text = selection Then
                RadioButtonList1.Items(i).Selected = True
                Exit For
            End If
        Next

    End Sub

End Class

希望你能在这里找到有用的东西。

动态创建radiobuttonlist

1 个答案: