Visual Studio :: Element 'content' Is Not A Known Element?
Nov 3, 2010
Element 'content' is not a known element. this can occur if there is a compilation error in the website, or the web.config file is missing.
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">
<asp:Content --- showed a green wavy line , and on hover displayed the above error.
Now I am having certain problems.
1. Visual Studio 2010 hangs when I try to use ToolBox.
2. Intellisense for asp.net controls is not working.
I have tried replacing web.config file (frm backup) , tried to debug - it doesnt show anything.
All other websites are working alright. Have problem with only one of the websites.
I'm looking at an asp.net application, i notice that there are assemblies defined into two places. In web.config there is configuration/system.web/compilation/assemblies/add elements. In the project file there are references setup under the Project/ItemGroup/Reference elements.
I was wondering, what is the difference between assemblies/references added in either location?
This doesn't happen when I create the site in my local drive. Is there a workaround to this. Even if I add the missing parts, I keep getting the same error.
I would like to select an element that is in the same TR as another element I found with a selector. The selector itself: $("input[name='sMessageValue']","#messageTable") Now I have this element and got its value I would like to find a checkbox located in the same TR, i tried this as starting point : $(this).(':parent').val(). But seems not the right thing to do.
You're making a website with ASP.NET 4.0/C#, although xml alone is suitable for this example. The site will have a site map and a default page with a menu control, as follows:Web.sitemap
I have vs2005 Pro, vs2008 Pro and vs2010 Pro installed on a Vista machine. Recently I upgraded a non-AJAX web site from vs2008 to vs2010. The web site works fine but now I'd like to use the UpdatePanel. However after I insert the ScriptManager I receive
the following error:
"Element 'ScriptManager' is not a known element. This can occur if there is a compilation error in the Web site, or the web.config file is missing."
All the posts I have read seem that I should not see this error in vs2010. I have even added the following to the web.config with no success:
[Code]....
As a side note, I am able to use the latest AJAX Control Toolkit for .NET 4.
I upgraded from VS 2008 to VS 2010 and now the AJAX elements are not recognised by the source code editor, e.g. UpdatePanel, ScriptManager, etc. I get warnings in VS and no intellisense for those elements. When I run the site, all the AJAX controls work OK though.
I got this errors while trying to use an example from the ASP.NET 3.5 Unleashed book.
Webform1.aspx
[Code]....
LengthValidator.cs
[Code]....
As from the book's note, I think I added this line correctly:
[Code]....
However, the compiler kept complaining that:
Warning 1 Element 'LengthValidator' is not a known element. This can occur if there is a compilation error in the Web site, or the web.config file is missing. C:Visual Studio 2010 ASP.NET ProjectsWebApplicationFourWebApplicationFourWebForm1.aspx 16 17 WebApplicationFour
I am using dotnetCHARTING: the dll is installed in the GAC and referenced in my web.config (all versions appear to match). The project has a reference to the dll.
The site code compiles ok, but all aspx pages using the charting library complain that the Chart tag does not exist (warning that it might be a compile error). The aspx pages do not render the charts.
Element 'AsyncPostBackTrigger' is not a known element. This can occur if there is a compilation error in the Web site, or the web.config file is missing.
My app is working properly but visual studio showing warning like that.
"JQueryPage.aspx" is just a page that contain DIV called 'resultsDIV' that contain the data that i want to return the above code return data variable that contain "JQueryPage.aspx" html and i want to get DIV content from it .
i have 2 questions:
1- how can i extract DIV content from data object 2- is this way is th best to get that data ?
I get some URL from a XML feed. Now the question is how do I get a specific data from each page represented by those URLs. For example if I have a URL: [URL] in the feed data and on that page there is a table like this:
[code]...
Now the question is how do I get the content of the span which has the class "summary" and which is the child of the having a class name "snip". We do have to decode emove the encoded html contained by the span.
I converted a forms website into an application and everything has been working just fine until now. I keep getting the green squiggly lines and the error that Element 'X' is not a known element. This is on almost every element, Gridview, Label, Update Panel, Hyperlink Field, Bound Field, etc...
so ajax and asp are viable prefixes. The very odd thing is that it is only happening on a few user controls, all other user controls are fine and the errors never show up. I have tried rebooting and everything and nothing seems to fix it. All masterpages, web paages, and about 90% of the user controls are fine, its only on a few user controls and super annoying!
All I want to do is access the <body> element from the code-behind of a content page and add a class name to it.
I have a top-level master page with the <body> element in it. Then I have a nested master page which is the master page for the content page. From the code behind of the content page I want to add a class name to the body element. That's all.
I have this in the top-level master:
<body id="bodyNode" runat="server">
I added this to the code-behind for the content page:
Anybody else find the web page editor for Visual Studios (2008) to be horribly buggy? Almost every other time I try to debug a program, it sputters around for a minute or two, and then I get this error: Unable to Start Program [URL]. Element not found. Sometimes it happens two or three times in a row, and each time it leaves a hung browser I have to go and end the process for and then try again, so it can get up to 10 minutes at times just to get the damn debugger going. Really frustrating, especially when it's at the end of the day and I'm trying to finish things up.
