private HttpResponseMessage CreateCheckCodeImage(string checkCode) { HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK); if (checkCode == null || checkCode.Trim() == String.Empty) return result; var image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)), 22); var g = Graphics.FromImage(image); try { //生成随机生成器 var random = new Random(); //清空图片背景色 g.Clear(Color.White); //画图片的背景噪音线 for (var i = 0; i < 25; i++) { var x1 = random.Next(image.Width); var x2 = random.Next(image.Width); var y1 = random.Next(image.Height); var y2 = random.Next(image.Height); g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2); } var font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic)); var brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true); g.DrawString(checkCode, font, brush, 2, 2); //画图片的前景噪音点 for (var i = 0; i < 100; i++) { var x = random.Next(image.Width); var y = random.Next(image.Height); image.SetPixel(x, y, Color.FromArgb(random.Next())); } //画图片的边框线 g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1); var ms = new System.IO.MemoryStream(); image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif); result.Content = new ByteArrayContent(ms.ToArray()); result.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("image/Gif"); return result; } finally { g.Dispose(); image.Dispose(); } } 