The 'CssRewriteUrlTransform' works just fine for applications that DON'T run on top of a virtual directory.
So, if your app runs on http://your-site.com/ it runs just fine, but if it runs on http://your-site.com/your-app/ you'll have 404 for all your images because the default 'CssFixRewriteUrlTransform' is referencing your images with a '/'.
To solve this issue, I have implemented my own version of 'CssRewriteUrlTransform' like this:
public class CssFixRewriteUrlTransform : IItemTransform {
private static string ConvertUrlsToAbsolute(string baseUrl, string content) {
if (string.IsNullOrWhiteSpace(content)) {
return content;
}
var regex = new Regex("url\\(['\"]?(?<url>[^)]+?)['\"]?\\)");
return regex.Replace(content, match => string.Concat("url(", RebaseUrlToAbsolute(baseUrl, match.Groups["url"].Value), ")"));
}
public string Process(string includedVirtualPath, string input) {
if (includedVirtualPath == null) {
throw new ArgumentNullException("includedVirtualPath");
}
var directory = VirtualPathUtility.GetDirectory(includedVirtualPath);
return ConvertUrlsToAbsolute(directory, input);
}
private static string RebaseUrlToAbsolute(string baseUrl, string url) {
if (string.IsNullOrWhiteSpace(url) || string.IsNullOrWhiteSpace(baseUrl) || url.StartsWith("/", StringComparison.OrdinalIgnoreCase)) {
return url;
}
if (!baseUrl.EndsWith("/", StringComparison.OrdinalIgnoreCase)) {
baseUrl = string.Concat(baseUrl, "/");
}
return VirtualPathUtility.ToAbsolute(string.Concat(baseUrl, url));
}
}
UPDATE: thanks to superjos who pointed out that there was another solution out there:
public class CssRewriteUrlTransformWrapper : IItemTransform
{
public string Process(string includedVirtualPath, string input)
{
return new CssRewriteUrlTransform().Process("~" + VirtualPathUtility.ToAbsolute(includedVirtualPath), input);
}
}
font-facerules. Should it? – Gradin