Access hidden asp.net objects

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tshad - 10 Sep 2007 16:58 GMT

How do you hide an asp.net object and still be able to access it?

I had my email in a session variable, but you can't access the session
variable from Javascript (I don't think - since Javascript is Client and
Session is Server).

I tried using the email that was on the page, but it was surrounded by a
Panel that had its visible property set to false - so anything inside of the
Panel was not on the page.

I also tried to set a variable:

<asp:Label ID="emailSave" Visible="false" runat="server"/>

But I had the same problem as the Panel, it wasn't on the page.

I am trying to access this from a page I open so this page is now the
opener.

How can I hide a variable and still get access to it via the Javascript?

Thanks,

Tom

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Patrice - 10 Sep 2007 17:08 GMT

Not sure what you mean by "hidding". You can render this value as an hidden
field or by rendering dynamically created JavaScript so that this is usable
client side (in both cases "view source" will reveal the value).

What do you do with this value ? If you don't need this client side, just
retrieve this server side at will rather than passing this value to the
client just to postback the value to the server...

---
Patrice

> How do you hide an asp.net object and still be able to access it?
>
[quoted text clipped - 20 lines]
>
> Tom

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tshad - 10 Sep 2007 17:16 GMT

> Not sure what you mean by "hidding". You can render this value as an
> hidden field or by rendering dynamically created JavaScript so that this
[quoted text clipped - 3 lines]
> retrieve this server side at will rather than passing this value to the
> client just to postback the value to the server...

I am trying to do this to get access from Javascript (clientSide) to my
variables on my parent page.

The problem is that if I do something like:

<asp:Panel ID="EmailPanel" visible=false runat="server">
<asp:TextBox ID=Email runat="server"/>
</asp:Panel>

or

<asp:Label ID="EmailSave" Visible=false/>

In either case, the variables do not seem to be on the page so JavaScript
can't see them.

I need this value to put onto the page that I am opening up.

Thanks,

Tom

> ---
> Patrice
[quoted text clipped - 23 lines]
>>
>> Tom

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Patrice - 10 Sep 2007 17:26 GMT

Expected. When you set visible to false server side it is not rendered at
all in the resulting HTML code (unlike using display:none for example).

http://msdn2.microsoft.com/en-us/library/system.web.ui.clientscriptmanager.regis
terhiddenfield.aspx
allows to easily render an hidden field (and as said earlier, note that view
source is enoguh to show its content).

---
Patrice

>> Not sure what you mean by "hidding". You can render this value as an
>> hidden field or by rendering dynamically created JavaScript so that this
[quoted text clipped - 54 lines]
>>>
>>> Tom

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Eliyahu Goldin - 10 Sep 2007 17:10 GMT

Server controls with Visible=false don't get rendered to client. Leave
Visible=true and hide with css rule display:none.

Signature

Eliyahu Goldin,
Software Developer
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
http://usableasp.net

> How do you hide an asp.net object and still be able to access it?
>
[quoted text clipped - 20 lines]
>
> Tom

Reply to this Message

tshad - 10 Sep 2007 18:16 GMT

> Server controls with Visible=false don't get rendered to client. Leave
> Visible=true and hide with css rule display:none.

That worked great.

If I set the Panel display:none, will it work the same way and hide the
controls but leave them on the page?

Is there a way to set this from vb.net during processing?

I periodically set visible to false to hide a control or section of HTML
with controls on them. This is usually done by <Div id="something"
runat=false> or <asp:Panel id = "something" runat=false> and then setting
something.visible=false.

This works pretty well most of the time.

But sometimes I do need to get access to the variables from Javascript - so
visible=false won't work.

So where I do something like this to hide panel in my asp.net code:

thePanel.visible = false

Is there a better way to do this so I can get access to the variables from
the panel?

How would I set style="display:none" from asp.net?

Thanks,

Tom

>> How do you hide an asp.net object and still be able to access it?
>>
[quoted text clipped - 20 lines]
>>
>> Tom

Reply to this Message

Eliyahu Goldin - 10 Sep 2007 19:44 GMT

> If I set the Panel display:none, will it work the same way and hide the
> controls but leave them on the page?

Yes

> How would I set style="display:none" from asp.net?

The easiest thing would be to make a css class

.Invisible{display:none}

Then you could set

something.CssClass="Invisible"

or

something.Attributes("class")="Invisible".

You also can do

something.Attributes("style")="display:none"

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tshad - 10 Sep 2007 22:33 GMT

>> If I set the Panel display:none, will it work the same way and hide the
>> controls but leave them on the page?
[quoted text clipped - 16 lines]
>
> something.Attributes("style")="display:none"

That's what I needed to know.

Thanks,

Tom

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Access hidden asp.net objects

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