如何覆盖或扩展.net主类.例如 @H_404_2@public class String { public boolean contains(string str,boolean IgnoreCase){...} public string replace(string str,string str2,boolean IgnoreCase){...} }

后

@H_404_2@string aa="this is a Sample"; if(aa.contains("sample",false)) {...}

可能吗？