Grinn / ThePirat 解决方案效果很好。
我不喜欢它在 bundle 上新增了 Include 方法，并且它在内容目录中创建了临时文件。 （他们最终被签入、部署，然后服务无法启动！）
所以为了遵循 Bundling 的设计，我选择执行基本相同的代码，但在 IBundleTransform 实现中：：
class StyleRelativePathTransform
: IBundleTransform
{
public StyleRelativePathTransform()
{
}
public void Process(BundleContext context, BundleResponse response)
{
response.Content = String.Empty;
Regex pattern = new Regex(@"url\s*\(\s*([""']?)([^:)]+)\1\s*\)", RegexOptions.IgnoreCase);
// open each of the files
foreach (FileInfo cssFileInfo in response.Files)
{
if (cssFileInfo.Exists)
{
// apply the RegEx to the file (to change relative paths)
string contents = File.ReadAllText(cssFileInfo.FullName);
MatchCollection matches = pattern.Matches(contents);
// Ignore the file if no match
if (matches.Count > 0)
{
string cssFilePath = cssFileInfo.DirectoryName;
string cssVirtualPath = context.HttpContext.RelativeFromAbsolutePath(cssFilePath);
foreach (Match match in matches)
{
// this is a path that is relative to the CSS file
string relativeToCSS = match.Groups[2].Value;
// combine the relative path to the cssAbsolute
string absoluteToUrl = Path.GetFullPath(Path.Combine(cssFilePath, relativeToCSS));
// make this server relative
string serverRelativeUrl = context.HttpContext.RelativeFromAbsolutePath(absoluteToUrl);
string quote = match.Groups[1].Value;
string replace = String.Format("url({0}{1}{0})", quote, serverRelativeUrl);
contents = contents.Replace(match.Groups[0].Value, replace);
}
}
// copy the result into the response.
response.Content = String.Format("{0}\r\n{1}", response.Content, contents);
}
}
}
}
然后将其封装在一个 Bundle 实现中：
public class StyleImagePathBundle
: Bundle
{
public StyleImagePathBundle(string virtualPath)
: base(virtualPath)
{
base.Transforms.Add(new StyleRelativePathTransform());
base.Transforms.Add(new CssMinify());
}
public StyleImagePathBundle(string virtualPath, string cdnPath)
: base(virtualPath, cdnPath)
{
base.Transforms.Add(new StyleRelativePathTransform());
base.Transforms.Add(new CssMinify());
}
}
示例用法：
static void RegisterBundles(BundleCollection bundles)
{
...
bundles.Add(new StyleImagePathBundle("~/bundles/Bootstrap")
.Include(
"~/Content/css/bootstrap.css",
"~/Content/css/bootstrap-responsive.css",
"~/Content/css/jquery.fancybox.css",
"~/Content/css/style.css",
"~/Content/css/error.css",
"~/Content/validation.css"
));
这是我的 RelativeFromAbsolutePath 扩展方法：
public static string RelativeFromAbsolutePath(this HttpContextBase context, string path)
{
var request = context.Request;
var applicationPath = request.PhysicalApplicationPath;
var virtualDir = request.ApplicationPath;
virtualDir = virtualDir == "/" ? virtualDir : (virtualDir + "/");
return path.Replace(applicationPath, virtualDir).Replace(@"\", "/");
}