Understanding problem: How to add a stylesheet to a web part

Question

Well, I try to add a css stylesheet to my web part but it didn’t work… I read that there are many ways to a css file into a web part, but I didn’t understand them….

First I installed the Sharepoint 2010 Tools, to create a visual web part for sandboxing. After that I created an empty project and added a visual web part (sandbox) to the project. Just after that, I created a new folder in the visual web part and added the stylesheet file to them.

Now I will add this css file to my web part, but I don’t know how…

I read, that this I possible with:

<SharePoint:CssRegistration runat="server" Name="./Styles/Site.css" />

But Visual Studio tells me, that an assembly for ::Microsoft.SharePoint.WebControls.CssRegistration is missing.

I use also use using Microsoft.SharePoint;

What is the best way, to import a css file to a web part? The css file should just available for this web part.

It would be awesome, if someone could help me to understand, how to include a stylesheet.

Information: CssRegistration: Available in Sandboxed Solutions: No!

Greetz

Answer 1

Another method to add the CSS is to create the CssRegistration object in the C# codebehind for the web part, and add your instance of CssRegistration to the web part's control hierarchy using this.ChildControls.Add().

You'll need to ensure this code is done within CreateChildControls override of the web part.

Answer 2

If you also will need to add JS code, consider using the ScriptManager. See my answer on that topic here