I have a control that has an embedded CSS file.
I override the  OnPreRender event and put in the following code:

HtmlLink cssLink = new HtmlLink();
.....  get the resource, create the link
Page.Header.Controls.Add(cssLink);
base.OnPreRender(e);

This works fine at runtime.
However at design time the CSS does not get applied.

Whats the best way to get the CSS applied at design time?

thanks,

Hi Chuck,

This is a quick note to let you know that I am performing research on this 
issue and will get back to you as soon as possible. I appreciate your 
patience. 


Regards,
Walter Wang (wawang@online.microsoft.com, remove 'online.')
Microsoft Online Community Support

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I guess OnPreRender doesn't fire in design mode.

http://www.manuelabadia.com/blog/PermaLink,guid,8cdc7001-bca7-4ea6-a3f8-0fb2861548f6.aspx

Hi Chuck,

Yes my test also verified that OnPreRender is not called in design-time. 
I'm also tried other approaches but still no luck, I'm currently consulting 
this question within our internal discussion list. I'll keep you posted. 
Thank you for your patience.

Regards,
Walter Wang (wawang@online.microsoft.com, remove 'online.')
Microsoft Online Community Support

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Hi Chuck,

It seems we will have to use a custom control designer to make the 
stylesheet work at design-time, and we must use inline style instead:

        public override string GetDesignTimeHtml()
        {
            return "<style> .highlight {background-color: yellow} </style>" 
+ base.GetDesignTimeHtml();
        }

This is not very elegant but so far this seems the only way to make the 
stylesheet works at design-time.

Regards,
Walter Wang (wawang@online.microsoft.com, remove 'online.')
Microsoft Online Community Support

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Thanks Walter,
I wasn't aware of that event.
I did something similar with checking for Design mode in the render event 
and putting in a link to an embedded style sheet.

        private string GetCssLink()
        {  
            string strFooterCssLocation = CssLocation; //empty unless user 
overrides location from the embedded style sheet

            if (string.IsNullOrEmpty(strFooterCssLocation))
                strFooterCssLocation = 
Page.ClientScript.GetWebResourceUrl(this.GetType(), 
@"Util_Controls.LanlFooter.css");

            return strFooterCssLocation;
        }


        protected override void RenderContents(HtmlTextWriter output)
        {
            if (DesignMode)
            {  //at runtime PreRender is fired and we put the link in the head
                output.Write(" <link href=\"" + GetCssLink() + "\" 
rel=\"stylesheet\" type=\"text/css\" />");
            }

Hi Chuck,

Thanks for sharing your solution here. I think it's better than having to 
write a custom control designer.

Regards,
Walter Wang (wawang@online.microsoft.com, remove 'online.')
Microsoft Online Community Support

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