Master Pages, Themes and Navigation Controls

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

darko.romanov — Mon, 07 Sep 2009 08:40:37 GMT

Same headache here, no one of the solutions in this forum worked for me, the only one was to start a new brand Master and then to use that one.

EDIT: it started to do the same with the new Master, predictable. I'm in trouble.

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

brucef — Tue, 07 Jul 2009 12:58:51 GMT

I had the same problem and tried your solution. It worked! I don't log the error, I just leave the Catch empty; and the code in the Try also does work, just like yours. My code is C#, so the problem is definitely language-independent (which is probably not a big surprise!)

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

vijeya — Wed, 01 Jul 2009 15:23:45 GMT

Today for some unknown reason, the TFS crashed. Since then I started getting the above error. The environment is Windows Server 2003, .NET 3.5, VS 2008. The above solution worked for me. I simply changed MasterPage to System.Web.UI.MasterPage on both the sides.

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

Mikecrosoft — Thu, 04 Jun 2009 16:22:39 GMT

Hi there :D,

I always do the next solution:

1. Close all VS Instances (kill all aspnet_wp.exe process),

2. Delete my project name folder of the above Directory

C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files

and the Compiler needs to Recompile everything again

3. Open your solution again rebuild

and voilaa !!

Fixed ;):

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

ketanbece — Tue, 02 Dec 2008 17:32:20 GMT

i just found solution during googleing

just go there.

http://dotnet-magic.blogspot.com/2008/12/unable-to-cast-object-of-type-asptype.html

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

ketanbece — Tue, 02 Dec 2008 17:25:43 GMT

Hello There Just Go outFollowing Solution

i found during googeling.

http://dotnet-magic.blogspot.com/2008/12/unable-to-cast-object-of-type-asptype.html

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

hc1 — Tue, 28 Oct 2008 02:18:53 GMT

I am getting this like as described in the first report of 2006.

I am merely copying the files onto the server (2003 R2) that is causing the problem. Even though the server has VWD, I am not using VWD there. The masterpage file is unchanged, still dated August and has been running fine since then until today.

The odd thing is that on this server I have two virtual directorys set up for the same code. One is staging and one is production. The staging one is giving the problem. I dare not restart the server as I don't want the problem to come up in the production folder instead.

I am on .NET 3.5 and my VWD on my PC is 2008. Do I still need the patch?

BTW: setting Compilation batch=false resolves the problem for the moment.

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

runax — Sat, 18 Oct 2008 02:57:35 GMT

I am able to reproduce the issue on a consistant basis. If I put some code in an aspx file that is not detected as invalid by Vs, after the site compiles, it produces the error. For example, in my ASPX file, I have a template field for a gridview like so:

<asp:TemplateField headertext="Size0">
<itemtemplate>
<asp:textbox id="txtSize0" runat="server" columns="2" maxlength="1" text='<% #IsNull(DataBinder.Eval(Container.DataItem,"Size0Group"),"") %>'></asp:textbox>
</itemtemplate>
</asp:TemplateField>

However, the function IsNull is in a class that is not referrenced in this aspx file nor in the codefile. Each time I add the above IsNull function, it bombs with the "cannot convert masterpage to type masterpage" issue. If I remove the line, it runs fine. Oddly enough, if I add a reference to the class that has that function, it still bombs.

Here is the function:

Public Function IsNull(ByVal data As Object, ByVal replaceValue As Object) As Object
If data.GetType Is GetType(DBNull) Then Return replaceValue Else Return data
End Function

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

serpilboyraz — Tue, 05 Aug 2008 11:09:23 GMT

System.Web.UI.MasterPage

instead of MasterPage worked for me too.

Thanks...

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

marcopolo007 — Tue, 24 Jun 2008 18:56:46 GMT

Scott,

Thanks for the help, but in my case this patch could not be installed and the <<batch = "false">> trick worked for a while but the cast exception appeared again. I believe my problem is coming from the fact that I am trying to load the usercontrol from two distinct other usercontrols not in the same path from the root, but I hope I am wrong as usercontrol has been implemented for that purpose. Unfortunately it is working perfectly fine once I moved the second repeater at the same path location from the root as the first one !!!! Please explain if there is an explanation for this behavior or I just got lucky and the cast exception will reappear again sometime later.

Thanks in advance,

Marc

(Code extracted below)

//In MyControl.ascx in the folder "AJAXControls"

public partial class AJAXControls_MyControl : System.Web.UI.UserControl

{

public static AJAXControls_MyControl LoadMe(Page _page, int _userid, bool _readonly)

{

AJAXControls_MyControl _myctrl = (AJAXControls_MyControl) _page.LoadControl("~/AJAXControls/MyControl.ascx");
_myctrl.UserID = _userid;

_myctrl.ReadOnly = _readonly;
return _myctrl;

}

}

//It is called from Repeater1.ascx in the folder "AJAXControls"

//and it is working with NO exceptions!

public partial class AJAXControls_RepeaterControl1 : System.Web.UI.UserControl

{

protected void Page_Load(object sender, EventArgs e)
{

if (!IsPostBack)
{

PlaceHolder _ph = (PlaceHolder)_item.FindControl("phItem");if (_ph != null)
{

_ph.Controls.Add(AJAXControls_MyControl.LoadMe(this.Page,this.UserId, this.ReadOnly));

}

}

else

{

}

}

}

//It is called from Repeater2.ascx in the folder "AJAXControls\SubReport"

//and it is error out with cast exceptions inside the "AJAXControls_MyControl" code behind!

public partial class AJAXControls_RepeaterControl2 : System.Web.UI.UserControl

{

protected void Page_Load(object sender, EventArgs e)
{

if (!IsPostBack)
{

PlaceHolder _ph = (PlaceHolder)_item.FindControl("phItem");if (_ph != null)
{

_ph.Controls.Add(AJAXControls_MyControl.LoadMe(this.Page, this.UserId, this.ReadOnly));

}

}

else

{

}

}

}

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

Elrinth — Mon, 19 May 2008 12:50:04 GMT

I have no idea why this happens. But like everyone else says it fixes itself when I update a file in the site.

When I get the error, it's not the masterpage itself, it's when I'm trying to cast a loaded control (LoadControl), a acsx file that is to the correct object-type. And as everyone else, it only happens randomly when I've changed the code.

Another error I'm getting is that the page simply doesn't load. I can see a VIEWSTATE which is DAAAANG large too. Anyone have a clue why this happens randomly?

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

BaySoft_Dan — Thu, 15 May 2008 10:08:30 GMT

has anyone found a reason for this error yet? It would be easier to come up with a suitable solution if the cause of the error was properly understood.

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

nablesgirl — Sat, 10 May 2008 11:17:19 GMT

Hi... I'm using System.web.UI.MsterPage Class To make a reference to my masterPage

put I found a better way to do it....

that was my code

System.Web.UI.MasterPage MyMasterPage=(masterpage)this.master;

but now i put the

<%@ MasterType virtualPath="~/MainMasterPage.master"%>

in the source code of the content page

then in the code i didn't cast to master page any more

System.Web.UI.MasterPage MyMasterPage=

MyMasterPage = ((System.Web.UI.MasterPage)this.Master)

this.Master.UserName = UserNameLabel.Text

in this way the error of (unable to cast Masterpage type...)

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

dlaney — Fri, 09 May 2008 18:19:16 GMT

I'm a little confused. I reference the master page with just Master. Where are you getting MasterPage from?

Re: Unable to cast object of type 'ASP.masterpage_master' to type 'ASP.masterpage_master'.

Gery128 — Thu, 08 May 2008 06:12:40 GMT

yeah..!

that worked for me also.