Master Page Dynamic CSS changes from content page

Change css from a content page that is a child of a Master Page

[mdsww]

Hi,

I have multiple sites in my application, each identified uniquely with a SiteID. I have enabled URLRewriting to look up the content for each request dynamically.

The issue I am now faced with is how to hide or show DIVs on my Master Page dynamically from the content aspx page.

Currently I can update a label from my aspx page with the following:

AppMaster.master

<asp:Label ID="lblMenu" runat="server" Text="Test"></asp:Label>

AppMaster.master.cs

public string MasterPageMenuLabel
{
get { return lblMenu.Text; }
set { lblMenu.Text = value; }
}

Content.aspx:

<%@ MasterType VirtualPath="~/AppMasterTest.master" %>

Content.aspx.cs:

Master.MasterPageMenuLabel = intSiteID.ToString();

This works fine if I want to pass a simple string and update a label. (In my example I am populating a label with the SiteID number.)

What I would like to do is turn on or off a DIV's Visible property with an ID using a similar method (or better).

The SiteID will determine which menu to show or hide. Currently this is the only way I can think of, given my relative lack of experience with ASP.Net and c#. (I have primarily programmed in Classic ASP VBScript and PHP).

I was thinking of doing a select case on the SiteID, and then firing the appropriate command to show/hide the correct DIVs....
div1 (contains menu for Site1)
div2 (contains menu for Site2)
div3 (contains menu for Site3)....

Something like:

if SiteID = 1 then turn on div1

Can someone please help me fill in the blanks?
Thank you in advance.

[Ocean10000]

The way you described it is very similar how I have one of my sites except I use custom user controls instead of divs so I can further customize the displays.

But for simple menu's I think what you are doing will work fine and will be easy enough for you to manage.

[mdsww]

Hi Ocean,

How do I reference the div and set it's display css property from the Content.aspx.cs?

<div id="menu1">
...
</div>
<div id="menu2">
...
</div>
<div id="menu3">
...
</div>
<div id="menu4">
...
</div>

Thank you.

[mdsww]

I got it working with the following:

if (intSiteID == 1) 
{
 this.Master.FindControl("menu1").Visible = true;
 this.Master.FindControl("menu2").Visible = false;
 this.Master.FindControl("menu3").Visible = false;
 this.Master.FindControl("menu4").Visible = false;
}
else if (intSiteID == 2)
{
 this.Master.FindControl("menu1").Visible = false;
 this.Master.FindControl("menu2").Visible = true;
 this.Master.FindControl("menu3").Visible = false;
 this.Master.FindControl("menu4").Visible = false;
}
else if (intSiteID == 3)
{
 this.Master.FindControl("menu1").Visible = false;
 this.Master.FindControl("menu2").Visible = false;
 this.Master.FindControl("menu3").Visible = true;
 this.Master.FindControl("menu4").Visible = false;
}
else if (intSiteID == 4)
{
 this.Master.FindControl("menu1").Visible = false;
 this.Master.FindControl("menu2").Visible = false;
 this.Master.FindControl("menu3").Visible = false;
 this.Master.FindControl("menu4").Visible = true;
}

I want to do this in 2 lines but this is the only way I got it working. Also I am unsure whether

this.Master.FindControl

is a performance overhead?

[marcel]

To make your above code a little easier to maintain when changing the menus, you could condense it to the following:

this.Master.FindControl("menu1").Visible = (intSiteID == 1);
this.Master.FindControl("menu2").Visible = (intSiteID == 2);
this.Master.FindControl("menu3").Visible = (intSiteID == 3);
this.Master.FindControl("menu4").Visible = (intSiteID == 4);

I usually use placholders for this kind of thing, like this

<asp:PlaceHolder ID="plcMenu1" runat="server">
...
</asp:PlaceHolder>

and make it visible/non-visible like this:

plcMenu1.Visible = (intSiteID == 1)

[mdsww]

Thank you, that is exactly what I was looking for!

I still am unclear if this is a performance overhead given it has iterate through the controls:

this.Master.FindControl("menu1")

...as I note that you do not reference the Master page in your final example.

[marcel]

Oh sorry, I should have been more clear on that. Because the menu is on the MasterPage I usually show/hide the elements in CodeBehind of the MasterPage itself, and not from a subpage.

You could use a public property (eg. intSiteId) on the MasterPage and use that to display the Menu's. Just update that value from Content.aspx.cs

So basically:
MasterPage

private int _siteId;
public int SiteId
{
get { return _siteId; }
set { _siteId = value; }
}

and in Page_PreRender (I usually use Prerender for this and not PageLoad, as the Property SiteId may not yet have been set at the PageLoad point)

plcMenu1.Visible = (_siteId == 1)
plcMenu2.Visible = (_siteId == 2)
plcMenu3.Visible = (_siteId == 3)
plcMenu4.Visible = (_siteId == 4)

And then from Content.aspx.cs

Master.SiteId = intSiteId;

I'm not completely sure of your setup though, maybe the master page already knows the siteId, or maybe I've interpreted it completely wrong.

hope this helps though.