HELP with ASP.NET DropDownList Box ! : )

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  1. #1

    Default HELP with ASP.NET DropDownList Box ! : )

    Hi all,

    I have a DropDownList on my page created in Design Time calledddlDate. In
    code, I do the following:

    1 ddlDate = New DropDownList() <- To Clear the drop down list
    2 ddlDate.Items.Add("HELLO")
    3 ddlDate.Items.Add("WORLD")

    When the page loads, how come my drop downlist is empty? Shouldn't there be
    two entries?

    If I remove Line 1, then the entries are present. However, logically
    speaking, why does Line 1 mess things up?

    Thanks!


    --
    Lucas Tam (REMOVEnntp@rogers.com)
    Please delete "REMOVE" from the e-mail address when replying.
    [url]http://members.ebay.com/aboutme/coolspot18/[/url]
    Lucas Tam Guest

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  3. #2

    Default Re: HELP with ASP.NET DropDownList Box ! : )

    This has worked for me beforfe, but its IE only I think

    Dim EncodedString As String = "This is a Test
    String"&#160;&#160;&#160;&#160;EndTestString"
    Dim writer As New System.IO.StringWriter()
    Server.HtmlDecode(EncodedString, writer)
    Dim DecodedString As String = writer.ToString()
    lstTest.Items.Add(DecodedString)

    --
    Regards

    John Timney (Microsoft ASP.NET MVP)
    ----------------------------------------------
    <shameless_author_plug>
    Professional .NET for Java Developers with C#
    ISBN:1-861007-91-4
    Professional Windows Forms
    ISBN: 1861005547
    Professional JSP 2nd Edition
    ISBN: 1861004958
    Professional JSP
    ISBN: 1861003625
    Beginning JSP Web Development
    ISBN: 1861002092
    </shameless_author_plug>
    ----------------------------------------------

    "Lucas Tam" <REMOVEnntp@rogers.com> wrote in message
    news:Xns93D096D9F2FDEnntprogerscom@207.46.248.16.. .
    > Hi all,
    >
    > I have a DropDownList on my page created in Design Time calledddlDate. In
    > code, I do the following:
    >
    > 1 ddlDate = New DropDownList() <- To Clear the drop down list
    > 2 ddlDate.Items.Add("HELLO")
    > 3 ddlDate.Items.Add("WORLD")
    >
    > When the page loads, how come my drop downlist is empty? Shouldn't there
    be
    > two entries?
    >
    > If I remove Line 1, then the entries are present. However, logically
    > speaking, why does Line 1 mess things up?
    >
    > Thanks!
    >
    >
    > --
    > Lucas Tam (REMOVEnntp@rogers.com)
    > Please delete "REMOVE" from the e-mail address when replying.
    > [url]http://members.ebay.com/aboutme/coolspot18/[/url]

    John Timney \(Microsoft MVP\) Guest

  4. #3

    Default Re: HELP with ASP.NET DropDownList Box ! : )

    Lucas,

    You say you are creating the drop down list dynamically. It sounds like you
    are creating the entries in the drop down dynamically, but that the list was
    added to the page in the design window.

    If this is the case then the drop down you are creating (the new one) is
    replacing the one in the design window and you aren't setting most of it's
    attributes.

    If it is the case that you have added the drop down to the page via the
    design window then instead of using "New" to clear the drop down do it like
    this:

    ddlDate.Items.Clear()

    Sincerely,

    --
    S. Justin Gengo, MCP
    Web Developer

    Free code library at:
    [url]www.aboutfortunate.com[/url]

    "Out of chaos comes order."
    Nietzche


    "Lucas Tam" <REMOVEnntp@rogers.com> wrote in message
    news:Xns93D096D9F2FDEnntprogerscom@207.46.248.16.. .
    > Hi all,
    >
    > I have a DropDownList on my page created in Design Time calledddlDate. In
    > code, I do the following:
    >
    > 1 ddlDate = New DropDownList() <- To Clear the drop down list
    > 2 ddlDate.Items.Add("HELLO")
    > 3 ddlDate.Items.Add("WORLD")
    >
    > When the page loads, how come my drop downlist is empty? Shouldn't there
    be
    > two entries?
    >
    > If I remove Line 1, then the entries are present. However, logically
    > speaking, why does Line 1 mess things up?
    >
    > Thanks!
    >
    >
    > --
    > Lucas Tam (REMOVEnntp@rogers.com)
    > Please delete "REMOVE" from the e-mail address when replying.
    > [url]http://members.ebay.com/aboutme/coolspot18/[/url]

    S. Justin Gengo Guest

  5. #4

    Default Re: HELP with ASP.NET DropDownList Box ! : )

    "S. Justin Gengo" <sjgengo@aboutfortunate.com> wrote in
    news:#ac3lWRXDHA.1744@TK2MSFTNGP12.phx.gbl:
    > If this is the case then the drop down you are creating (the new one)
    > is replacing the one in the design window and you aren't setting most
    > of it's attributes.
    Yes exactly! That is what I am doing.

    > If it is the case that you have added the drop down to the page via
    > the design window then instead of using "New" to clear the drop down
    > do it like this:
    >
    > ddlDate.Items.Clear()
    However, shouldn't using New() to clear also work? Logically speaking,
    shouldn't new() bind a new instance to the control? I wonder why it won't
    pick up the newly bound control.

    BTW, your suggestion worked great! Thanks for your help!

    --
    Lucas Tam (REMOVEnntp@rogers.com)
    Please delete "REMOVE" from the e-mail address when replying.
    [url]http://members.ebay.com/aboutme/coolspot18/[/url]
    Lucas Tam Guest

  6. #5

    Default Re: HELP with ASP.NET DropDownList Box ! : )

    Lucas,

    It's because other settings are defined by the page.

    Take a look in the web for designer generated code area of the codebehind
    page.

    You'll see the following:

    Private Sub Page_Init(ByVal sender As System.Object, ByVal e As
    System.EventArgs) Handles MyBase.Init
    'CODEGEN: This method call is required by the Web Form Designer
    'Do not modify it using the code editor.
    InitializeComponent()
    End Sub

    The routine above actually runs setup routines for the components on your
    page. When you called "New" you overwrote all those "Hidden" settings. If
    declare a new component you have to recreate them.

    Sincerely,

    --
    S. Justin Gengo, MCP
    Web Developer

    Free code library at:
    [url]www.aboutfortunate.com[/url]

    "Out of chaos comes order."
    Nietzche


    "Lucas Tam" <REMOVEnntp@rogers.com> wrote in message
    news:Xns93D09964BD103nntprogerscom@207.46.248.16.. .
    > "S. Justin Gengo" <sjgengo@aboutfortunate.com> wrote in
    > news:#ac3lWRXDHA.1744@TK2MSFTNGP12.phx.gbl:
    >
    > > If this is the case then the drop down you are creating (the new one)
    > > is replacing the one in the design window and you aren't setting most
    > > of it's attributes.
    >
    > Yes exactly! That is what I am doing.
    >
    >
    > > If it is the case that you have added the drop down to the page via
    > > the design window then instead of using "New" to clear the drop down
    > > do it like this:
    > >
    > > ddlDate.Items.Clear()
    >
    > However, shouldn't using New() to clear also work? Logically speaking,
    > shouldn't new() bind a new instance to the control? I wonder why it won't
    > pick up the newly bound control.
    >
    > BTW, your suggestion worked great! Thanks for your help!
    >
    > --
    > Lucas Tam (REMOVEnntp@rogers.com)
    > Please delete "REMOVE" from the e-mail address when replying.
    > [url]http://members.ebay.com/aboutme/coolspot18/[/url]

    S. Justin Gengo Guest

  7. #6

    Default Re: HELP with ASP.NET DropDownList Box ! : )

    sorry Lucas, I appear to have replied to the wrong post here

    --
    Regards

    John Timney (Microsoft ASP.NET MVP)
    ----------------------------------------------
    <shameless_author_plug>
    Professional .NET for Java Developers with C#
    ISBN:1-861007-91-4
    Professional Windows Forms
    ISBN: 1861005547
    Professional JSP 2nd Edition
    ISBN: 1861004958
    Professional JSP
    ISBN: 1861003625
    Beginning JSP Web Development
    ISBN: 1861002092
    </shameless_author_plug>
    ----------------------------------------------

    "John Timney (Microsoft MVP)" <timneyj@despammed.com> wrote in message
    news:u$SIwWRXDHA.1896@TK2MSFTNGP12.phx.gbl...
    > This has worked for me beforfe, but its IE only I think
    >
    > Dim EncodedString As String = "This is a Test
    > String"&#160;&#160;&#160;&#160;EndTestString"
    > Dim writer As New System.IO.StringWriter()
    > Server.HtmlDecode(EncodedString, writer)
    > Dim DecodedString As String = writer.ToString()
    > lstTest.Items.Add(DecodedString)
    >
    > --
    > Regards
    >
    > John Timney (Microsoft ASP.NET MVP)
    > ----------------------------------------------
    > <shameless_author_plug>
    > Professional .NET for Java Developers with C#
    > ISBN:1-861007-91-4
    > Professional Windows Forms
    > ISBN: 1861005547
    > Professional JSP 2nd Edition
    > ISBN: 1861004958
    > Professional JSP
    > ISBN: 1861003625
    > Beginning JSP Web Development
    > ISBN: 1861002092
    > </shameless_author_plug>
    > ----------------------------------------------
    >
    > "Lucas Tam" <REMOVEnntp@rogers.com> wrote in message
    > news:Xns93D096D9F2FDEnntprogerscom@207.46.248.16.. .
    > > Hi all,
    > >
    > > I have a DropDownList on my page created in Design Time calledddlDate.
    In
    > > code, I do the following:
    > >
    > > 1 ddlDate = New DropDownList() <- To Clear the drop down list
    > > 2 ddlDate.Items.Add("HELLO")
    > > 3 ddlDate.Items.Add("WORLD")
    > >
    > > When the page loads, how come my drop downlist is empty? Shouldn't there
    > be
    > > two entries?
    > >
    > > If I remove Line 1, then the entries are present. However, logically
    > > speaking, why does Line 1 mess things up?
    > >
    > > Thanks!
    > >
    > >
    > > --
    > > Lucas Tam (REMOVEnntp@rogers.com)
    > > Please delete "REMOVE" from the e-mail address when replying.
    > > [url]http://members.ebay.com/aboutme/coolspot18/[/url]
    >
    >

    John Timney \(Microsoft MVP\) Guest

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