public static void AppendQueryArgs(this UriBuilder builder, IEnumerable<KeyValuePair<string, string>> args)
{
if (args != null && args.Any())
{
StringBuilder sb = new StringBuilder(50 + (args.Count() * 10));
if (!string.IsNullOrEmpty(builder.Query))
{
sb.Append(builder.Query.Substring(1));
sb.Append('&');
}
sb.Append(CreateQueryString(args));
builder.Query = sb.ToString();
}
}