CODEWITHSUNDEEP
asp.netvb.net
user3636426
user3636426

Reputation: 177

Call an aspx method from ascx

The ASPX that I have is a partial that has a a master page on it and I would like to replace a textbox with new text.

I have a listbox that is created from the data base in the ASCX. I have a text box in the default.aspx page which I would like to change the test if the selected index has changed. I keep getting the error to delcare class, the class definiton for the defualt.aspx.vb is got a definition is below. 

Partial Class _Default
    Inherits System.Web.UI.Page

Code that sits on default.aspx.vb

Public Sub test(ByVal val As String)

    lbl1LoginPage.Text = val
End Sub

VB ascx code to get the value of the selected index

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

Upvotes: 0

Views: 1347

Answers (3)

Win
Win

Reputation: 62260

UserControl should not call Parent page. It is not a good design.

Instead, you want to bubble up the event from UserControl to the Parent page.

Here is the example -

Child

<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

Parent

<%@ 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

Upvotes: 0

ibram
ibram

Reputation: 4569

My suggestion is to use a bubble event:

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

this is all in C#!! here is your method in your aspx-page:

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 );
}

Upvotes: 1

Jags
Jags

Reputation: 782

You can create a Property in aspx page exposing the text box control say "TextBoxControl" then you can access it in you dropdownlist handler as shown below :

 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

(I am not well versed with vb.net so syntax may be wrong at some places)

Upvotes: 1

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