ASP.NETで、IEとFirefoxがファイルをダウンロードして漢字名の時に文字化けしの解決方法を持ちます

解決策:

HttpContext.Current.Response.Clear();

HttpContext.Current.Response.Buffer = true;

HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");

HttpContext.Current.Response.Charset = "gb2312";

HttpContext.Current.Response.AddHeader("Content-Disposition", string.Format("attachment; filename={0}.xls", string.IsNullOrEmpty(fileName) ? DateTime.Now.ToString("yyyyMMddHHmmssfff") : System.Web.HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8)));

HttpContext.Current.Response.BinaryWrite(ms.ToArray());

HttpContext.Current.Response.End();

しかし、上記の方法はfirefoxでは文字化けしています.
 
究極の解決策:

                Encoding encoding;

                string outputFileName = null;

                string browser = HttpContext.Current.Request.UserAgent.ToUpper();

                if (browser.Contains("MS") == true && browser.Contains("IE") == true)

                {

                    outputFileName = HttpUtility.UrlEncode(fileName);

                    encoding = System.Text.Encoding.Default;

                }

                else if (browser.Contains("FIREFOX") == true)

                {

                    outputFileName = fileName;

                    encoding = System.Text.Encoding.GetEncoding("GB2312");

                }

                else

                {

                    outputFileName = HttpUtility.UrlEncode(fileName);

                    encoding = System.Text.Encoding.Default;

                }

                HttpContext.Current.Response.Clear();

                HttpContext.Current.Response.Buffer = true;

                HttpContext.Current.Response.ContentEncoding = encoding;

                HttpContext.Current.Response.AddHeader("Content-Disposition", string.Format("attachment; filename={0}.xls", string.IsNullOrEmpty(outputFileName) ? DateTime.Now.ToString("yyyyMMddHHmmssfff") : outputFileName));

                HttpContext.Current.Response.BinaryWrite(ms.ToArray());

                HttpContext.Current.Response.End();