Question

我拥有的ASPX是一个部分，其上有一个母版页，我想用新文本替换文本框。

我有一个从ASCX中的数据库创建的列表框。我在default.aspx页面中有一个文本框，如果所选索引已更改，我想更改测试。我一直得到delcare类的错误，defualt.aspx.vb的类定义如下定义。

Partial Class _Default
    Inherits System.Web.UI.Page

位于default.aspx.vb上的代码

Public Sub test(ByVal val As String)

    lbl1LoginPage.Text = val
End Sub

VB ascx代码获取所选索引的值

Protected Sub ListBox3_SelectedIndexChanged(sender As Object, e As System.EventArgs) Handles ListBox3.SelectedIndexChanged

    Dim test As String = ListBox3.Text
    Dim page As _Default = DirectCast(page, _Default)
    page.test(test)
End Sub

Answer 1

你可以在aspx页面中创建一个属性，公开文本框控件说＆＃34; TextBoxControl＆＃34;然后你可以在你的下拉列表处理程序中访问它，如下所示：

 Protected Sub ListBox3_SelectedIndexChanged(sender As Object, e As System.EventArgs) Handles ListBox3.SelectedIndexChanged

Dim test As String = ListBox3.Text
Dim page As _Default = DirectCast(Me.Page, _Default)
page.TextBoxControl.Text = "Some Text"
End Sub

（我对vb.net并不熟悉，所以在某些地方语法可能有问题）

Answer 2

我的建议是使用气泡事件：

Protected Sub ListBox3_SelectedIndexChanged(sender As Object, e As System.EventArgs) Handles ListBox3.SelectedIndexChanged

    Dim test As String = ListBox3.Text
    // this line is in C#. I don't know how it is in VB
    RaiseBubbleEvent( this, new CommandEventArgs( "ListBoxText", test ) );
End Sub

这一切都在C＃!!这是你的aspx页面中的方法：

protected override bool OnBubbleEvent( object source, EventArgs args )
{
    // you can check in addition whether the source is of type of your user control
    if ( args is CommandEventArgs )
    {
        lbl1LoginPage.Text = ((CommandEventArgs)args ).CommandArgument.ToString();
        return true;
    }

    return base.OnBubbleEvent( source, args );
}

Answer 3

UserControl 不应调用父页面。这不是一个好的设计。

相反，您希望冒泡从 UserControl 到父页面。

以下是示例 -

子

<asp:ListBox runat="server" ID="ListBox3" 
    OnSelectedIndexChanged="ListBox3_SelectedIndexChanged"
    AutoPostBack="True">
    <asp:ListItem>Item 1</asp:ListItem>
    <asp:ListItem>Item 2</asp:ListItem>
</asp:ListBox>

Public Partial Class Child
    Inherits System.Web.UI.UserControl
    Public Event ListBox3SelectedIndexChanged As EventHandler

    Protected Sub ListBox3_SelectedIndexChanged(sender As Object, e As EventArgs)
        RaiseEvent ListBox3SelectedIndexChanged(sender, e)
    End Sub
End Class

父

<%@ Register Src="~/Child.ascx" TagName="Child" TagPrefix="uc1" %>

...

<uc1:Child ID="Child1" runat="server" 
   OnListBox3SelectedIndexChanged="Child1_ListBox3SelectedIndexChanged" />

Protected Sub Child1_ListBox3SelectedIndexChanged(sender As Object, 
    e As EventArgs)
    Dim listBox3 = TryCast(sender, ListBox)
    If listBox3 IsNot Nothing Then
        Dim selectedText As String = listBox3.SelectedItem.Text
    End If
End Sub

从ascx调用aspx方法

3 个答案:

子

父