ResolveUrls without page reference. Makes rooted relative urls. Has very simple syntax with anonymous objects for query string params.

gistfile1.txt

public static string GlobalResolveUrl(string url)
{
    return (new Uri(HttpContext.Current.Request.Url, ResolveUrl(url))).GetLeftPart(UriPartial.Query);
}

public static string GlobalResolveUrl(string url, object queryStringParams)
{
    return (new Uri(HttpContext.Current.Request.Url, ResolveUrl(url, queryStringParams))).GetLeftPart(UriPartial.Query);
}

public static string ResolveUrl(string url)
{
    if (!url.StartsWith("~/")) return url;
    var appDomainAppVirtualPath = HttpRuntime.AppDomainAppVirtualPath;
    var resolved = url.Substring(1);
    return appDomainAppVirtualPath == "/" ? resolved : appDomainAppVirtualPath + resolved;
}

public static string ResolveUrl(string url, object queryStringParams)
{
    var sb = new StringBuilder(ResolveUrl(url));
    bool firstParam = !url.Contains("?");
    foreach (var p in queryStringParams.ToDictionary())
    {
        sb.Append(firstParam ? '?' : '&');
        sb.Append(HttpUtility.UrlEncode(p.Key));
        firstParam = false;
        if (p.Value == null) continue;
        sb.Append('=');
        sb.Append(HttpUtility.UrlEncode(p.Value.ToString()));
    }
    return sb.ToString();
}

public static Dictionary<string, object> ToDictionary(this object values)
{
    return values == null ? null : TypeDescriptor.GetProperties(values).Cast<PropertyDescriptor>().ToDictionary(a => a.Name, a => a.GetValue(values));
}