登录页面上的验证码的生成

  


  1 
  2 
  3 using System;
  4 using System.Data;
  5 using System.Configuration;
  6 using System.Collections;
  7 using System.Web;
  8 using System.Web.Security;
  9 using System.Web.UI;
 10 using System.Web.UI.WebControls;
 11 using System.Web.UI.WebControls.WebParts;
 12 using System.Web.UI.HtmlControls;
 13 
 14 
 15 
 16 public partial class _Default : System.Web.UI.Page
 17 {
 18 
 19     private static string sValidator = "";
 20     private readonly string sValidatorImageUrl = "ValidateImage.aspx?Validator=";
 21 
 22     private static char[] allCharArray = new char[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
 23 
 24 
 25 
 26     protected void Page_Load(object sender, EventArgs e)
 27     {
 28         this.tbUserName.Focus();
 29 
 30         if (!Page.IsPostBack)
 31         {
 32             sValidator=CreateValidateString(6);
 33 
 34             Application["validateString"] = sValidator;
 35 
 36             this.imgValidator.ImageUrl=sValidatorImageUrl+sValidator;
 37         }
 38     }
 39 
 40     //随机生成验证码，并把验证码保存到Session中
 41     private string CreateValidateString(int nLen)
 42     {
 43         #region 0-9数字的验证码
 44 
 45         string randomCode = "";
 46         int t = 0;
 47 
 48         Random rand = new Random();
 49 
 50         for (int i = 0; i < nLen; i++)
 51         {
 52             t = rand.Next(9);
 53 
 54             randomCode += allCharArray[t];
 55         }
 56 
 57         Session["CheckCode"] = randomCode;
 58 
 59         return randomCode;
 60 
 61         #endregion
 62     }
 63 
 64     protected void btnCancel_Click(object sender, EventArgs e)
 65     {
 66         this.tbUserName.Text = "";
 67         this.tbPassword.Text = "";
 68         this.lbMessage.Text = "";
 69 
 70 
 71         sValidator = CreateValidateString(6);
 72 
 73         Application["validateString"] = sValidator;
 74 
 75         this.imgValidator.ImageUrl = sValidatorImageUrl + sValidator;
 76 
 77 
 78 
 79         this.imgValidator.ImageUrl = sValidatorImageUrl + sValidator;
 80 
 81     }
 82 
 83     protected void btnLogin_Click(object sender, EventArgs e)
 84     {
 85         if (Page.IsValid == true)
 86         {
 87             if (this.tbValidator.Text != sValidator)
 88             {
 89                 lbMessage.Text = "验证码输入错误，请重新输入验证码！！！";
 90 
 91                 sValidator = CreateValidateString(6);
 92 
 93                 Application["validateString"] = sValidator;
 94 
 95                 this.imgValidator.ImageUrl = sValidatorImageUrl + sValidator;
 96 
 97                 return;
 98             }
 99             else
100             {
101                 Response.Write("congradulations!");
102             }
103         }
104 
105     }
106   
107 }

108 
109 //***************************************************************************
110 using System;
111 using System.Data;
112 using System.Configuration;
113 using System.Collections;
114 using System.Web;
115 using System.Web.Security;
116 using System.Web.UI;
117 using System.Web.UI.WebControls;
118 using System.Web.UI.WebControls.WebParts;
119 using System.Web.UI.HtmlControls;
120 
121 using System.Drawing;
122 using System.Drawing.Imaging;
123 
124 
125 public partial class ValidateImage : System.Web.UI.Page
126 {
127 
128     #region 设置验证码
129     private int codeLen = 6;//验证码长度
130 
131     private int fineness = 90;//图片清晰度
132 
133     private int imgWidth = 60;//图片宽度
134 
135     private int imgHeight = 18;//图片高度
136 
137     private string fontFamily = "Arial";//字体家庭名称
138 
139     private int fontSize = 11;//字体大小
140 
141     private int fontStyle = 1;//字体样式
142 
143     private int posX = 5;//绘制起始坐标X
144 
145     private int posY = 2;//绘制起始坐标Y
146 
147     //private static char[] allCharArray = new char[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
148     #endregion
149 
150     protected void Page_Load(object sender, EventArgs e)
151     {
152         #region 读取Request 传递参数
153         //获取代码长度设置
154         if (Request["CodeLen"] != null)
155         {
156             try
157             {
158                 codeLen = Int32.Parse(Request["CodeLen"]);
159                 //规定验证码长度
160                 if (codeLen < 4 || codeLen > 16)
161                 {
162                     throw new Exception("验证码长度必须在4到16之间");
163                 }
164            
165             }
166             catch (Exception Ex)
167             {
168                 throw Ex;
169             }
170         }
171 
172             //获取图片清晰度设置
173             if (Request["Fineness"] != null)
174             {
175                 try
176                 {
177                     fineness = Int32.Parse(Request["Fineness"]);
178 
179                     //验证清晰度
180                     if (fineness < 0 || fineness > 100)
181                         throw new Exception("图片清晰度必须在0到100之间");
182                 }
183                 catch (Exception Ex)
184                 {
185                     throw Ex;
186                 }
187             }
188             
189                 //获取图片宽度
190                 if (Request["ImgWidth"] != null)
191                 {
192                     try
193                     {
194                         imgWidth = Int32.Parse(Request["ImgWidth"]);
195 
196                         if (imgWidth < 16 || imgWidth > 480)
197                             throw new Exception("图片宽度必须在16到480之间");
198                     }
199                     catch (Exception Ex)
200                     {
201                         throw Ex;
202                     }
203                 }
204 
205 
206                 //获取图片高度
207                 if (Request["ImgHeight"] != null)
208                 {
209                     try
210                     {
211                         imgWidth = Int32.Parse(Request["ImgHeight"]);
212 
213                         if (imgWidth < 16 || imgWidth > 320)
214                             throw new Exception("图片高度必须在16到320之间");
215                     }
216                     catch (Exception Ex)
217                     {
218                         throw Ex;
219                     }                   
220                 }
221 
222             
223                     //获取验证码字体家族名称
224                     if (Request["FontFamily"] != null)
225                     {
226                         fontFamily = Request["FontFamily"];
227                     }
228 
229 
230             
231                     //获取验证码字体大小
232                     if (Request["FontSize"] != null)
233                     {
234                         try
235                         {
236                             fontSize = Int32.Parse(Request["FontSize"]);
237 
238                             if (fontSize < 8 || fontSize > 72)
239                             {
240                                 throw new Exception("字体大小必须在8到72之间");
241                             }
242                         }
243                         catch (Exception Ex)
244                         {
245                             throw Ex;
246                         }
247                     }
248                    
249 
250              //获取字体样式
251                     if (Request["FontStyle"] != null)
252                     {
253                         try
254                         {
255                             fontStyle = Int32.Parse(Request["FontStyle"]);
256                         }
257                         catch (Exception Ex)
258                         {
259                             throw Ex;
260                         }
261                     }
262 
263              //验证码绘制起始位置X
264                     if (Request["PosX"] != null)
265                     {
266                         try
267                         {
268                             posX = Int32.Parse(Request["PosX"]);
269                         }
270                         catch (Exception Ex)
271                         {
272                             throw Ex;
273                         }
274                     }
275 
276              //验证码绘制起始位置Y
277                     if (Request["PosY"] != null)
278                     {
279                         try
280                         {
281                             posY = Int32.Parse(Request["PosY"]);
282                         }
283                         catch (Exception Ex)
284                         {
285                             throw Ex;
286                         }
287                     }
288         #endregion  读取Request 传递参数
289 
290        //string validateCode = CreateValidateCode();
291 
292         string validateCode = Application["validateString"].ToString();
293 
294     
295        //生成Bitmap图像
296        Bitmap bitmap = new Bitmap(imgWidth, imgHeight);
297 
298         //给图像设置干扰
299        DisturbBitmap(bitmap);
300 
301         //绘制验证码
302        DrawValidateCode(bitmap, validateCode);
303 
304         //保存验证码图像，等待输出
305        bitmap.Save(Response.OutputStream, ImageFormat.Gif);
306 
307        bitmap.Dispose();
308      }
309 
310     ////随机生成验证码，并把验证码保存到Session中
311     //private string CreateValidateCode()
312     //{
313     //    #region 0-9数字的验证码
314 
315     //    string randomCode = "";
316     //    int t = 0;
317 
318     //    Random rand = new Random();
319 
320     //    for (int i = 0; i < codeLen; i++)
321     //    {
322     //        t = rand.Next(9);
323 
324     //        randomCode += allCharArray[t];
325     //    }
326 
327     //    Session["CheckCode"] = randomCode;
328 
329     //    return randomCode;
330 
331     //    #endregion 
332     //}
333 
334     //为图片设置干扰
335     private void DisturbBitmap(Bitmap bitmap)
336     {
337         //通过随机数生成
338         Random random = new Random();
339 
340         for (int i = 0; i < bitmap.Width; i++)
341         {
342             for (int j = 0; j < bitmap.Height; j++)
343             {
344                 if (random.Next(100) <= this.fineness)
345                     bitmap.SetPixel(i, j, Color.White);
346             }
347         }
348     }
349 
350 
351     //绘制验证码图片
352     private void DrawValidateCode(Bitmap bitmap, string validateCode)
353     {
354         //获取绘制器对象
355 
356         Graphics g = Graphics.FromImage(bitmap);
357 
358         //绘制字体
359         Font font = new Font(fontFamily, fontSize, GetFontStyle());
360 
361         //绘制验证码图像
362         g.DrawString(validateCode, font, Brushes.Black, posX, posY);
363 
364         font.Dispose();
365         g.Dispose();
366     }
367 
368 
369     //换算验证码字体样式：1粗体 2斜体 3粗斜体，默认为普通字体
370 
371     private FontStyle GetFontStyle()
372     {
373         if (fontStyle == 1)
374         {
375             return FontStyle.Bold;
376         }
377         else if (fontStyle == 2)
378         {
379             return FontStyle.Italic;
380         }
381         else
382         {
383             return FontStyle.Regular;
384         }
385     }
386 }
387