asp.net-mvc – Web API的压缩过滤器

http://msdn.microsoft.com/en-us/magazine/gg232768.aspx

我已经尝试重新使用代码来做类似于Web API的操作，但是我遇到了一个路障：

public class CompressAPIAttribute : System.Web.Http.Filters.ActionFilterAttribute
{
    public override void OnActionExecuting(System.Web.Http.Controllers.HttpActionContext filterContext)
    {
        var preferredEncoding = GetPreferredEncoding(filterContext.Request);
        Stream compressedStream = null;
        // Compress the response accordingly
        var response = filterContext.Response;
        response.Headers.Add("Content-encoding",preferredEncoding.ToString());

        if (preferredEncoding == CompressionScheme.Gzip)
        {
            response.Content = new GZipStream(compressedStream,CompressionMode.Compress); //THIS WON'T WORK
        } 

        if (preferredEncoding == CompressionScheme.Deflate)
        {
            response.Content = new DeflateStream(compressedStream,CompressionMode.Compress); //THIS WON'T WORK
        }
        return;
    }

    enum CompressionScheme
    {
        Gzip = 0,Deflate = 1,Identity = 2
    }

    private CompressionScheme GetPreferredEncoding(HttpRequestMessage request)
    {
        var acceptableEncoding = request.Headers.AcceptEncoding;

        if (acceptableEncoding.Where(h => h.Value.Contains("gzip")).Count() > 0)
            return CompressionScheme.Gzip;

        if (acceptableEncoding.Where(h => h.Value.Contains("deflate")).Count() > 0)
            return CompressionScheme.Deflate;

        return CompressionScheme.Identity;
    }

任何想法，我如何可以分配一个压缩流到响应的内容？

我应该指出这是托管在IIS 6.0，我不控制。