关于Graphics也有了基本了解下面想说的的是学这个东东干什么呢，到底如何应用
目前常见应用1、验证码（参照网上的）2、打印排版（会提到关于条形码大小设置）3、自定义控件一、验证码
1 class ValidateCode 2 { 3 #region 定义和初始化配置字段 4 5 //用户存取验证码字符串 6 public string validationCode = String.Empty; 7 8 //生成的验证码字符串 9 public char[] chars = null; 10 11 /// 12 /// 获取随机验证码 13 /// 14 public String ValidationCode 15 { 16 get { return validationCode; } 17 } 18 19 /// 20 /// 验证码字符串的长度 21 /// 22 private Int32 validationCodeCount = 4; 23 24 /// 25 /// 获取和设置验证码字符串的长度 26 /// 27 public Int32 ValidationCodeCount 28 { 29 get { return validationCodeCount; } 30 set { validationCodeCount = value; } 31 } 32 33 /// 34 /// 画板对象 35 /// 36 Graphics dc = null; 37 38 //验证码的宽度，默认为130 39 private int bgWidth = 130; 40 41 /// 42 /// 验证码的宽度，默认为130 43 /// 44 public Int32 Width 45 { 46 get { return bgWidth; } 47 set { bgWidth = value; } 48 } 49 50 //验证码的宽度，默认为130 51 private int bgHeight = 40; 52 53 /// 54 /// 验证码的高度，默认为40 55 /// 56 public Int32 Height 57 { 58 get { return bgHeight; } 59 set { bgHeight = value; } 60 } 61 62 //字体大小 字体最小值 63 private int fontMinSize = 20; 64 65 /// 66 /// 验证码字体的最小值，默认为20,建议不小于15像素 67 /// 68 public Int32 FontMinSize 69 { 70 get { return fontMinSize; } 71 set { fontMinSize = value; } 72 } 73 //字体大小 字体最大值 74 private Int32 fontMaxSize = 25; 75 76 /// 77 /// 验证码字体的最大值，默认为25 78 /// 79 public Int32 FontMaxSize 80 { 81 get { return fontMaxSize; } 82 set { fontMaxSize = value; } 83 } 84 85 //验证码字体的颜色 86 private Color[] fontColor = { }; 87 88 /// 89 /// 验证码字体的颜色，默认为系统自动生成字体颜色 90 /// 91 public Color[] FontColor 92 { 93 get { return fontColor; } 94 set { fontColor = value; } 95 } 96 97 private Color backColor = Color.FromArgb(243, 255, 255); 98 99 /// 100 /// 验证码的背景色，默认为Color.FromArgb(243, 251, 254)101 /// 102 public Color BackgroundColor103 {104 get { return backColor; }105 set { backColor = value; }106 }107 108 //贝塞尔曲线的条数,默认为3条109 private Int32 bezierCount = 3;110 111 /// 112 /// 贝塞尔曲线的条数,默认为3条113 /// 114 public Int32 BezierCount115 {116 get { return bezierCount; }117 set { bezierCount = value; }118 }119 120 //直线条数，默认为3条121 private Int32 lineCount = 3;122 123 /// 124 /// 直线条数，默认为3条125 /// 126 public Int32 LineCount127 {128 get { return lineCount; }129 set { lineCount = value; }130 }131 132 //随机字符串列表133 private String charCollection = "2,3,4,5,6,7,8,9,a,s,d,f,g,h,z,c,v,b,n,m,k,q,w,e,r,t,y,u,p,A,S,D,F,G,H,Z,C,V,B,N,M,K,Q,W,E,R,T,Y,U,P"; //定义验证码字符及出现频次 ,避免出现0 o j i l 1 x; 134 135 /// 136 /// 随机字符串列表，请使用英文状态下的逗号分隔137 /// 138 public String CharCollection139 {140 get { return charCollection; }141 set { charCollection = value; }142 }143 144 //验证码字符串个数，默认为4个字符145 private Int32 intCount = 4;146 147 /// 148 /// 验证码字符串个数，默认为4个字符149 /// 150 public Int32 IntCount151 {152 get { return intCount; }153 set { intCount = value; }154 }155 156 //是否添加噪点，默认添加，噪点颜色为系统随机生成。157 private Boolean isPixel = true;158 /// 159 /// 是否添加噪点，默认添加，噪点颜色为系统随机生成。160 /// 161 public Boolean IsPixel162 {163 get { return isPixel; }164 set { isPixel = value; }165 }166 167 //是否添加随机噪点字符串，默认添加168 private Boolean isRandString = true;169 /// 170 /// 是否添加随机噪点字符串，默认添加171 /// 172 public Boolean IsRandString173 {174 get { return isRandString; }175 set { isRandString = value; }176 }177 178 /// 179 /// 随机背景字符串的个数180 /// 181 public Int32 RandomStringCount182 {183 get; set;184 }185 186 //随机背景字符串的大小187 private Int32 randomStringFontSize = 9;188 /// 189 /// 随机背景字符串的大小190 /// 191 public Int32 RandomStringFontSize192 {193 get { return randomStringFontSize; }194 set { randomStringFontSize = value; }195 }196 197 /// 198 /// 是否对图片进行扭曲199 /// 200 public Boolean IsTwist201 {202 get; set;203 }204 205 /// 206 /// 边框样式207 /// 208 public enum BorderStyle209 {210 /// 211 /// 无边框212 /// 213 None,214 /// 215 /// 矩形边框216 /// 217 Rectangle,218 /// 219 /// 圆角边框220 /// 221 RoundRectangle222 }223 224 /// 225 /// 验证码字符串随机转动的角度 默认40226 /// 227 private Int32 rotationAngle = 40;228 /// 229 /// 验证码字符串随机转动的角度的最大值230 /// 231 public Int32 RotationAngle232 {233 get { return rotationAngle; }234 set { rotationAngle = value; }235 }236 237 /// 238 /// 设置或获取边框样式239 /// 240 public BorderStyle Border241 {242 get; set;243 }244 245 /// 246 /// 对验证码图片进行高斯模糊的阀值，如果设置为0247 /// 248 private Double gaussianDeviation = 0;249 250 /// 251 /// 对验证码图片进行高斯模糊的阀值，如果设置为0，则不对图片进行高斯模糊，该设置可能会对图片处理的性能有较大影响252 /// 253 public Double GaussianDeviation254 {255 get { return gaussianDeviation; }256 set { gaussianDeviation = value; }257 }258 private Int32 brightnessValue = 0;259 /// 260 /// 对图片进行暗度和亮度的调整，如果该值为0，则不调整。该设置会对图片处理性能有较大影响261 /// 262 public Int32 BrightnessValue263 {264 get { return brightnessValue; }265 set { brightnessValue = value; }266 }267 268 #endregion269 270 271 private Point[] strPoint = null;272 273 Random random = new Random();274 275 /// 276 /// 构造函数，用于初始化常用变量277 /// 278 public void DrawValidationCode()279 {280 //随机对象 281 //Random类所取到的系统时钟种子接近甚至完全一样282 //解决方案：new Random(Guid.NewGuid().GetHashCode());283 random = new Random(Guid.NewGuid().GetHashCode());284 //坐标数组285 strPoint = new Point[validationCodeCount + 1];286 if (gaussianDeviation < 0)287 gaussianDeviation = 0;288 }289 290 /// 291 /// 生成验证码292 /// 思路：多张图片合成293 /// 1.验证码背景图片294 /// 1.1.背景包含295 /// 1.1.1.背景颜色296 /// 1.1.2.噪点297 /// 1.1.3.干扰文字298 /// 1.1.4.干扰线条（直线、曲线）299 /// 2.验证码字符300 /// 3.验证码图片扭曲301 /// 4.验证码图片模糊302 /// 5.验证码图片亮度303 /// 6.验证码图片保持在内存流中304 /// 305 /// 用于存储图片的一般字节序列306 public MemoryStream CreateImage(string code)307 {308 MemoryStream target = new MemoryStream();309 // 定义图片对象大小，310 Bitmap bit = new Bitmap(bgWidth + 1, bgHeight + 1);311 // 定义 Graphics（画板）根据图片对象 312 dc = Graphics.FromImage(bit);313 /*314 SmoothingModeAntiAlias 指定消除锯齿的呈现。315 SmoothingModeDefault 指定默认模式。316 SmoothingModeHighQuality 指定高质量、低速度呈现。317 SmoothingModeHighSpeed 指定高速度、低质量呈现。318 SmoothingModeInvalid 指定一个无效模式。319 SmoothingModeNone 指定不消除锯齿。320 */321 dc.SmoothingMode = SmoothingMode.HighQuality;322 //文本的呈现模式323 dc.TextRenderingHint = TextRenderingHint.ClearTypeGridFit;324 // 插补模式325 dc.InterpolationMode = InterpolationMode.HighQualityBilinear;326 //合成图像的呈现质量327 dc.CompositingQuality = CompositingQuality.HighQuality;328 try329 {330 //清空画板，指定背景色（白色）331 dc.Clear(Color.White);332 DrawValidationCode();333 //DrawImageUnscaled 在指定的位置使用图像的原始物理大小绘制指定的图像334 // 验证码背景335 dc.DrawImageUnscaled(DrawBackground(), 0, 0);336 // 验证码字符337 dc.DrawImageUnscaled(DrawRandomString(code), 0, 0);338 //对图片文字进行扭曲339 bit = AdjustRippleEffect(bit, 5);340 //对图片进行高斯模糊341 if (gaussianDeviation > 0)342 {343 Gaussian gau = new Gaussian();344 bit = gau.FilterProcessImage(gaussianDeviation, bit);345 }346 //进行暗度和亮度处理347 if (brightnessValue != 0)348 {349 //对图片进行调暗处理 350 bit = AdjustBrightness(bit, brightnessValue);351 }352 bit.Save(target, ImageFormat.Jpeg);353 //输出图片流 354 return target;355 356 }357 finally358 {359 //brush.Dispose(); 360 bit.Dispose();361 dc.Dispose();362 }363 }364 365 #region 画验证码背景，例如，增加早点，添加曲线和直线等 366 /// 367 /// 画验证码背景，例如，增加早点，添加曲线和直线等368 /// 1.1.背景包含369 /// 1.1.1.背景颜色370 /// 1.1.2.噪点371 /// 1.1.3.干扰文字372 /// 1.1.4.干扰线条（直线、曲线）373 /// 374 /// Bitmap 对象 375 private Bitmap DrawBackground()376 {377 Bitmap bit = new Bitmap(bgWidth + 1, bgHeight + 1);378 Graphics g = Graphics.FromImage(bit);379 g.SmoothingMode = SmoothingMode.HighQuality;380 g.Clear(Color.White);381 Rectangle rectangle = new Rectangle(0, 0, bgWidth, bgHeight);382 Brush brush = new SolidBrush(backColor);383 //填充矩形384 g.FillRectangle(brush, rectangle);385 //画噪点 386 if (isPixel)387 {388 g.DrawImageUnscaled(DrawRandomPixel(30), 0, 0);389 }390 // 背景干扰字符391 g.DrawImageUnscaled(DrawRandBgString(), 0, 0);392 //画曲线 393 //g.DrawImageUnscaled(DrawRandomBezier(bezierCount), 0, 0);394 //画直线 395 //g.DrawImageUnscaled(DrawRandomLine(lineCount), 0, 0);396 if (Border == BorderStyle.Rectangle)397 {398 //绘制边框 399 g.DrawRectangle(new Pen(Color.FromArgb(90, 87, 46)), 0, 0, bgWidth, bgHeight);400 }401 else if (Border == BorderStyle.RoundRectangle)402 {403 //画圆角 404 DrawRoundRectangle(g, rectangle, Color.FromArgb(90, 87, 46), 1, 3);405 }406 return bit;407 }408 #endregion409 410 #region 画随机噪点411 /// 412 /// 画随机噪点413 /// 在指定区域中随机设置像素点的颜色414 /// 415 /// 噪点的百分比 416 /// 445 /// 画背景干扰文字 446 /// 447 /// 490 /// 随机生成贝塞尔曲线 491 /// 492 /// 一个图片的实例 493 /// 线条数量 494 /// 537 /// 画直线 538 /// 539 /// 一个bmp实例 540 /// 线条个数 541 /// 565 /// 写入验证码的字符串 566 /// 567 private Bitmap DrawRandomString(string Code)568 {569 if (fontMaxSize >= (bgHeight / 5) * 4)570 throw new ArgumentException("字体最大值参数FontMaxSize与验证码高度相近，这会导致描绘验证码字符串时出错，请重新设置参数！");571 Bitmap b = new Bitmap(bgWidth, bgHeight);572 b.MakeTransparent();573 Graphics g = Graphics.FromImage(b);574 g.Clear(Color.Transparent);575 g.PixelOffsetMode = PixelOffsetMode.Half;576 g.SmoothingMode = SmoothingMode.HighQuality;577 g.TextRenderingHint = TextRenderingHint.SingleBitPerPixelGridFit;578 g.InterpolationMode = InterpolationMode.HighQualityBilinear;579 chars = Code.ToCharArray(); //拆散字符串成单字符数组 580 validationCode = chars.ToString();581 //设置字体显示格式 582 StringFormat format = new StringFormat(StringFormatFlags.NoClip);583 format.Alignment = StringAlignment.Center;584 format.LineAlignment = StringAlignment.Center;585 FontFamily f = new FontFamily(GenericFontFamilies.Monospace);586 Int32 charNum = chars.Length;587 Point sPoint = new Point();588 Int32 fontSize = 12;589 validationCodeCount = charNum;590 for (int i = 0; i < validationCodeCount; i++)591 {592 //定义字体 593 Font textFont = new Font(f, random.Next(fontMinSize, fontMaxSize), FontStyle.Bold);594 //定义画刷，用于写字符串 595 //Brush brush = new SolidBrush(GetRandomDeepColor()); 596 Int32 textFontSize = Convert.ToInt32(textFont.Size);597 fontSize = textFontSize;598 //Point point = new Point(random.Next((bgWidth / charNum) * i + 5, (bgWidth / charNum) * (i + 1)), random.Next(bgHeight / 5 + textFontSize / 2, bgHeight - textFontSize / 2));599 // 字符位置坐标600 Point point = new Point(random.Next((bgWidth / charNum) * i + 2, (bgWidth / charNum) * (i + 1) - (textFontSize / 2)), random.Next(bgHeight / 5 + textFontSize / 2, bgHeight - textFontSize / 2));601 //如果当前字符X坐标小于字体的二分之一大小 602 if (point.X < textFontSize / 2)603 {604 point.X = point.X + textFontSize / 2;605 }606 //防止文字叠加 607 if (i > 0 && (point.X - sPoint.X < (textFontSize / 2 + textFontSize / 2)))608 {609 point.X = point.X + textFontSize;610 }611 //如果当前字符X坐标大于图片宽度，就减去字体的宽度 612 if (point.X > (bgWidth - textFontSize / 2))613 {614 point.X = bgWidth - textFontSize / 2;615 }616 sPoint = point;617 float angle = random.Next(-rotationAngle, rotationAngle);//转动的度数 618 g.TranslateTransform(point.X, point.Y);619 g.RotateTransform(angle);620 621 Rectangle myretang = new Rectangle(0, 1, Convert.ToInt32(textFont.Size), Convert.ToInt32(textFont.Size));622 Color c = GetRandomDeepColor();623 //设置渐变画刷624 LinearGradientBrush mybrush2 = new LinearGradientBrush(myretang, c, GetLightColor(c, 120), random.Next(180));625 g.DrawString(chars[i].ToString(), textFont, mybrush2, 1, 1, format);626 627 g.RotateTransform(-angle);//转回去628 g.TranslateTransform(-point.X, -point.Y);//移动光标到指定位置，每个字符紧凑显示，避免被软件识别629 strPoint[i] = point;630 textFont.Dispose();631 mybrush2.Dispose();632 }633 return b;634 }635 #endregion636 637 #region 增加或減少亮度638 /// 639 /// 增加或減少亮度 640 /// 641 /// System.Drawing.Image Source 642 /// 0~255 643 /// 670 /// 水波纹效果 671 /// 672 /// 673 /// 坡度 674 /// www.it165.net 675 /// 759 /// 生成随机字符串 760 /// 761 /// 777 /// 生成随机深颜色 778 /// 779 /// 795 /// 生成随机浅颜色 796 /// 797 /// randomColor 798 public Color GetRandomLightColor()799 {800 int nRed, nGreen, nBlue;801 //越大颜色越浅 802 int low = 180; //色彩的下限 803 int high = 255; //色彩的上限 804 nRed = random.Next(high) % (high - low) + low;805 nGreen = random.Next(high) % (high - low) + low;806 nBlue = random.Next(high) % (high - low) + low;807 Color color = Color.FromArgb(nRed, nGreen, nBlue);808 return color;809 }810 /// 811 /// 获取与当前颜色值相加后的颜色 812 /// 813 /// 814 /// 838 /// C# GDI+ 绘制圆角矩形 839 /// 840 /// Graphics 对象 841 /// Rectangle 对象，圆角矩形区域 842 /// 边框颜色 843 /// 边框宽度 844 /// 圆角半径 845 private static void DrawRoundRectangle(Graphics g, Rectangle rectangle, Color borderColor, float borderWidth, int r)846 {847 // 如要使边缘平滑，请取消下行的注释 848 g.SmoothingMode = SmoothingMode.HighQuality; 849 Pen p = new Pen(borderColor, borderWidth);850 // 调用 getRoundRectangle 得到圆角矩形的路径，然后再进行绘制 851 g.DrawPath(p, getRoundRectangle(rectangle, r));852 }853 #endregion854 855 #region 根据普通矩形得到圆角矩形的路径 856 /// 857 /// 根据普通矩形得到圆角矩形的路径 858 /// 859 /// 原始矩形860 /// 半径 861 /// 图形路径 862 private static GraphicsPath getRoundRectangle(Rectangle rectangle, int r)863 {864 int l = 2 * r;865 // 把圆角矩形分成八段直线、弧的组合，依次加到路径中 866 GraphicsPath gp = new GraphicsPath();867 gp.AddLine(new Point(rectangle.X + r, rectangle.Y), new Point(rectangle.Right - r, rectangle.Y));868 gp.AddArc(new Rectangle(rectangle.Right - l, rectangle.Y, l, l), 270F, 90F);869 gp.AddLine(new Point(rectangle.Right, rectangle.Y + r), new Point(rectangle.Right, rectangle.Bottom - r));870 gp.AddArc(new Rectangle(rectangle.Right - l, rectangle.Bottom - l, l, l), 0F, 90F);871 gp.AddLine(new Point(rectangle.Right - r, rectangle.Bottom), new Point(rectangle.X + r, rectangle.Bottom));872 gp.AddArc(new Rectangle(rectangle.X, rectangle.Bottom - l, l, l), 90F, 90F);873 gp.AddLine(new Point(rectangle.X, rectangle.Bottom - r), new Point(rectangle.X, rectangle.Y + r));874 gp.AddArc(new Rectangle(rectangle.X, rectangle.Y, l, l), 180F, 90F);875 return gp;876 }877 #endregion878 } 调用
1 private void frmValidateCode_Load(object sender, EventArgs e)2 {3 ValidateCode vCode = new ValidateCode();4 string code = vCode.GetRandomString(5);5 MemoryStream stream = vCode.CreateImage(code);6 pictureBox1.Image = new Bitmap(stream);7 } 效果
