【类】随机验证码

这是一个随机生成验证码的类，具体调用方法：

1、先实例化一个类对象： VerificationNumImgUtility vnu = new VerificationNumImgUtility() ;

2、将获得的验证图片赋给PictrueBox或其他用来显示图片的控件即可：

     pictureBox1.ImageLocation = vnu.GenImageFile();

  1     /// <summary>
  2     /// 生成随机验证码类
  3     /// </summary>
  4     class VerificationNumImgUtility
  5     {
  6         #region 字段
  7         private int sumCharsOfVerNum = 4;
  8         private int imageWidth = 100;
  9         private int imageHeight = 30;
 10         private string imageName = "VerNum";
 11         private Font fontVerNum = new Font("Consolas", 14, FontStyle.Bold, GraphicsUnit.Pixel);
 12         #endregion
 13 
 14         #region 变量
 15         private SizeF[] charSizesOfVerNum;
 16         private string verNum;
 17         #endregion
 18 
 19         #region 常量
 20         private string[] charsToGenVerNum = { "0","1","2","3","4","5","6","7","8","9",
 21                                       "A","B","C","D","E","F","G","H","I","J",
 22                                       "K","L","M","N","O","P","Q","R","S","T",
 23                                       "U","V","W","X","Y","Z","a","b","c","d",
 24                                       "e","f","g","h","i","j","k","l","m","n",
 25                                       "o","p","q","r","s","t","u","v","w","x",
 26                                       "y","z"};
 27         #endregion
 28 
 29         #region 属性
 30         /// <summary>
 31         /// 验证码文件名称
 32         /// </summary>
 33         public string ImageName
 34         {
 35             get
 36             {
 37                 return this.imageName;
 38             }
 39             set
 40             {
 41                 this.imageName = string.IsNullOrEmpty(value) ? "VerNum" : value;
 42             }
 43         }
 44 
 45         /// <summary>
 46         /// 验证码的字符数
 47         /// </summary>
 48         public int SumCharsOfVerNum
 49         {
 50             get
 51             {
 52                 return this.sumCharsOfVerNum;
 53             }
 54             set
 55             {
 56                 this.sumCharsOfVerNum = value > 0 ? value : this.sumCharsOfVerNum;
 57             }
 58         }
 59 
 60         /// <summary>
 61         /// 图像宽度
 62         /// </summary>
 63         public int ImageWidth
 64         {
 65             get
 66             {
 67                 return this.imageWidth;
 68             }
 69             set
 70             {
 71                 this.imageWidth = value > 0 ? value : this.imageWidth;
 72             }
 73         }
 74 
 75         /// <summary>
 76         /// 图像高度
 77         /// </summary>
 78         public int ImageHeight
 79         {
 80             get
 81             {
 82                 return this.imageHeight;
 83             }
 84             set
 85             {
 86                 this.imageHeight = value > 0 ? value : this.imageHeight;
 87             }
 88         }
 89 
 90 
 91         /// <summary>
 92         /// 字符串的值
 93         /// </summary>
 94         public string VarString
 95         {
 96             get
 97             {
 98                 return this.verNum;
 99             }
100             set
101             {
102                 verNum = value;
103             }
104         }
105         /// <summary>
106         /// 设置字体
107         /// </summary>
108         public Font FontVerNum
109         {
110             get
111             {
112                 return this.fontVerNum;
113             }
114             set
115             {
116                 this.fontVerNum = value;
117             }
118         }
119         #endregion
120 
121         #region 构造函数
122         public VerificationNumImgUtility()
123             : this(4, 100, 30, "VerNum", "Consolas", 16)
124         { }
125 
126         public VerificationNumImgUtility(string imageName)
127             : this(4, 100, 30, imageName, "Consolas", 16)
128         { }
129 
130         public VerificationNumImgUtility(int imageWidth, int imageHeigh, string imageName)
131             : this(4, imageWidth, imageHeigh, imageName, "Consolas", 16)
132         { }
133 
134         public VerificationNumImgUtility(int sumCharsOfVerNum, int imageWidth, int imageHeight, string imageName, string fontName, float fontSize)
135         {
136             this.sumCharsOfVerNum = sumCharsOfVerNum;
137             this.imageWidth = imageWidth;
138             this.imageHeight = imageHeight;
139             this.imageName = imageName;
140             this.fontVerNum = new Font(fontName, fontSize, FontStyle.Bold, GraphicsUnit.Pixel);
141             this.charSizesOfVerNum = new SizeF[sumCharsOfVerNum];
142         }
143         #endregion
144 
145         /// <summary>
146         /// 产生随机验证码
147         /// </summary>
148         /// <returns>验证码数组</returns>
149         private string[] GenRandomChars()
150         {
151             Random r = new Random();
152             string[] genedCharsOfVerNum = new string[this.sumCharsOfVerNum];
153             verNum = "";
154             for (int i = 0; i < this.sumCharsOfVerNum; i++)
155             {
156                 int index = r.Next(0, charsToGenVerNum.Length);
157                 genedCharsOfVerNum[i] = charsToGenVerNum[index];
158 
159                 this.verNum = string.Concat(this.verNum, this.charsToGenVerNum[index]);
160             }
161 
162             return genedCharsOfVerNum;
163         }
164 
165         /// <summary>
166         /// 验证码每位的大小
167         /// </summary>
168         /// <param name="genedCharsOfVerNum">验证码数组</param>
169         /// <param name="g">当前图像类</param>
170         private void MeasureCharSizesOfVerNum(string[] genedCharsOfVerNum, Graphics g)
171         {
172             if (genedCharsOfVerNum == null)
173             {
174                 return;
175             }
176 
177             for (int i = 0; i < this.sumCharsOfVerNum; i++)
178             {
179                 this.charSizesOfVerNum[i] = g.MeasureString(genedCharsOfVerNum[i], this.fontVerNum);
180             }
181         }
182 
183         /// <summary>
184         /// 产生验证码的位置
185         /// </summary>
186         /// <returns></returns>
187         private Point[] GenRandomPostions()
188         {
189 
190             Random r = new Random();
191             string genedY = string.Empty;
192             Point[] genedCharPostionsOfVerNum = new Point[4];
193 
194             for (int i = 0; i < this.sumCharsOfVerNum; i++)
195             {
196                 genedCharPostionsOfVerNum[i].X = Convert.ToInt32(charSizesOfVerNum[i].Width / 2 + (Convert.ToDouble(this.imageWidth) - charSizesOfVerNum[i].Width * 2) / (sumCharsOfVerNum * 2) * (2 * i + 1));
197 
198 
199                 int maxY = this.imageHeight - Convert.ToInt32(charSizesOfVerNum[i].Height);
200                 int y = r.Next(0, maxY);
201 
202                 //保证y坐标都不同
203                 while (genedY.Contains(y.ToString()))
204                 {
205                     y = r.Next(0, maxY);
206                 }
207 
208                 genedY = string.Concat(genedY, ",", y);
209 
210                 genedCharPostionsOfVerNum[i].Y = y;
211             }
212 
213             return genedCharPostionsOfVerNum;
214         }
215 
216         /// <summary>
217         /// 生成BMP文件
218         /// </summary>
219         /// <returns>验证码字符串</returns>
220         public string GenImageFile()
221         {
222             return GenImageFile(ImageFormat.Bmp);
223         }
224 
225         /// <summary>
226         /// 生成文件，并打开
227         /// </summary>
228         /// <param name="f">文件类型</param>
229         /// <returns>验证码字符串</returns>
230         public string GenImageFile(ImageFormat f)
231         {
232             Bitmap bmpVerNum = GenBMPObject(this.sumCharsOfVerNum);
233             string path = Directory.GetCurrentDirectory() + "\\" + this.imageName + "." + f.ToString();
234 
235             try
236             {
237                 bmpVerNum.Save(path, f);
238             }
239             catch (Exception)
240             {
241                 ShowMessage("Error saving image file!", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);
242                 Environment.Exit(-1);
243             }
244             finally
245             {
246                 bmpVerNum.Dispose();
247             }
248 
249             //try
250             //{
251             //    Process.Start(path);
252             //}
253             //catch (Exception)
254             //{
255             //    ShowMessage("Error opening image file!", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);
256             //    Environment.Exit(-1);
257             //}
258 
259             return path;
260         }
261 
262         /// <summary>
263         /// 生成BMP文件对象
264         /// </summary>
265         /// <param name="sumCharsOfVerNum"></param>
266         /// <returns>BMP文件对象</returns>
267         private Bitmap GenBMPObject(int sumCharsOfVerNum)
268         {
269             Bitmap bmpVerNum = null;
270             try
271             {
272                 bmpVerNum = new Bitmap(this.imageWidth, this.imageHeight);
273             }
274             catch (SystemException)
275             {
276                 ShowMessage("Error creating bitmap file!", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Error);
277                 Environment.Exit(-1);
278             }
279 
280             Graphics graphicVerNumImg = Graphics.FromImage(bmpVerNum);
281             graphicVerNumImg.SmoothingMode = SmoothingMode.HighQuality;
282             graphicVerNumImg.FillRectangle(new SolidBrush(Color.White), 0, 0, this.imageWidth, this.imageHeight);
283 
284             string[] genedVerNums = GenRandomChars();
285             MeasureCharSizesOfVerNum(genedVerNums, graphicVerNumImg);
286             Point[] genedVerNumPositons = GenRandomPostions();
287 
288             for (int i = 0; i < sumCharsOfVerNum; i++)
289             {
290                 graphicVerNumImg.DrawString(genedVerNums[i], fontVerNum, new SolidBrush(Color.Tomato), genedVerNumPositons[i]);
291             }
292 
293             graphicVerNumImg.Dispose();
294 
295             return bmpVerNum;
296         }
297 
298         /// <summary>
299         /// 来自CodeProject，使提示框置顶
300         /// </summary>
301         /// <param name="message"></param>
302         /// <param name="title"></param>
303         /// <param name="buttons"></param>
304         /// <param name="icon"></param>
305         /// <returns></returns>
306         private DialogResult ShowMessage(string message, string title, MessageBoxButtons buttons, MessageBoxIcon icon)
307         { // Create a host form that is a TopMost window which will be the parent of the MessageBox.
308             Form topmostForm = new Form();
309             // We do not want anyone to see this window so position it off the visible screen and make it as small as possible
310             topmostForm.Size = new System.Drawing.Size(1, 1);
311             topmostForm.StartPosition = FormStartPosition.Manual;
312             System.Drawing.Rectangle rect = SystemInformation.VirtualScreen;
313             topmostForm.Location = new System.Drawing.Point(rect.Bottom + 10, rect.Right + 10);
314             topmostForm.Show();
315             // Make this form the active form and make it TopMost
316             topmostForm.Focus();
317             topmostForm.BringToFront();
318             topmostForm.TopMost = true;
319             // Finally show the MessageBox with the form just created as its owner
320             DialogResult result = MessageBox.Show(topmostForm, message, title, buttons, icon);
321             topmostForm.Dispose(); // clean it up all the way
322 
323             return result;
324         }
325     }