ie6处理下载文件名过长问题的解决方案（总结）

Response.HeaderEncoding = Encoding.UTF8;
Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(filename, Encoding.UTF8));
IE8下正常，IE6下有截断

Response.HeaderEncoding = Encoding.UTF8;
Response.AddHeader("Content-Disposition", "attachment;filename=" + filename);   // filename不做编码
所有IE下乱码

Response.HeaderEncoding = Encoding.GetEncoding("gb2312");
Response.AddHeader("Content-Disposition", "attachment;filename=" + filename);
IIS下时， 一切正常。 IE6下无截断。 但在webdev下，会有乱码

但有的符号出不来，如“#”