/// <summary> /// 获取一个验证码字串及PNG图片数据 /// </summary> /// <param name="length">验证码长度(4比较合适)</param> /// <param name="checkcode">随机生成的验证码字符串</param> /// <returns></returns> public static byte[] GetImage(int length, out string checkcode) { checkcode = RandomText.String(length); var random = new Random(); //注意,字体应该是所在操作系统中存在的字体 "Comic Sans MS" var font = new Font("Comic Sans MS", 20, FontStyle.Bold | FontStyle.Italic, GraphicsUnit.Pixel); var stringFormat = new StringFormat { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center }; using (var bitmap = new Bitmap((int)Math.Ceiling((double)(length * 18)), 27, PixelFormat.Format24bppRgb)) { using (var graphics = Graphics.FromImage(bitmap)) { graphics.Clear(Color.White); graphics.SmoothingMode = SmoothingMode.AntiAlias; graphics.TextRenderingHint = TextRenderingHint.AntiAlias; //画图片的背景噪音线 for (int i = 0; i < 5; i++) { int x1 = random.Next(bitmap.Width); int x2 = random.Next(bitmap.Width); int y1 = random.Next(bitmap.Height); int y2 = random.Next(bitmap.Height); graphics.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2); } graphics.DrawString(checkcode, font, Brushes.Black, new RectangleF(0f, 0f, (float)bitmap.Width, (float)bitmap.Height), stringFormat); //画图片的前景噪音点 for (int i = 0; i < 20; i++) { int x = random.Next(bitmap.Width); int y = random.Next(bitmap.Height); bitmap.SetPixel(x, y, Color.FromArgb(random.Next())); } } using (var bitmap2 = WaveDistortion(bitmap)) { using (var ms = new System.IO.MemoryStream()) { bitmap2.Save(ms, ImageFormat.Png); //bitmap2.Save("img.jpg"); return(ms.ToArray()); } } } }