public IActionResult VerifyCode() { #region 防止网页后退--禁止缓存 Response.Headers.Add("Cache-Control", "no-cache, no-store, must-revalidate"); // HTTP 1.1. Response.Headers.Add("Pragma", "no-cache"); // HTTP 1.0. Response.Headers.Add("Expires", "-1"); // Proxies. #endregion Random r = new Random(); string code = r.Next(10000, 100000).ToString(); SetSession(SessionSetting.AdminLoginCode, code); VerifyCode vimg = new VerifyCode(); vimg.FontSize = 30; var bytes = vimg.CreateImageBytes(code); var AcceptEncodings = Request.Headers["Accept-Encoding"].ToString().Replace(" ", "").Split(','); if (AcceptEncodings.Contains("br")) { Response.Headers["Content-Encoding"] = "br"; bytes = CompressionUtil.BrCompress(bytes, true); } else if (AcceptEncodings.Contains("gzip")) { Response.Headers["Content-Encoding"] = "gzip"; bytes = CompressionUtil.GzipCompress(bytes, true); } return(File(bytes, "image/jpg")); }