/ * Copyright all (c) 2005 ZhongFeng, http://blog.9cbs.net/SW515 * / public class ValidateCode: System.Web.UI.Page {private void Page_Load (object sender, System.EventArgs e) {this. CreateCheckcodeImage (GenerateCheckcode ());
#Region Web Form Designer Generated Code Override Protected Void OnNit (Eventargs E) {// // Codegen: This call is required for the ASP.NET Web Form Designer. // InitializeComponent (); base.onit (e);} ///
Private string generatecheckcode () {int number; char code; string checkcode = string.empty
System.random random = new random ();
For (int i = 0; i <5; i ) {Number = random.next ();
IF (Number% 2 == 0) Code = (CHAR) ('0' (Number% 10)); Else Code = (CHAR) ('a' (Number% 26));
Checkcode = Code.toString ();
Response.cookies.add (New Httpcookie ("Checkcode", Checkcode);
Return CHECKCODE;
Private void createcheckcodeImage (string checkcode) {if (checkcode == null || Checkcode.trim () == String.empty) Return;
System.drawing.bitmap image = new system.drawing.bitmap ((int) Math.ceiling (Checkcode.length * 12.5)), 22); graphics g = graphics.fromImage (image);
Try {// Generate Random Builder Random Random = New Random ();
// Empty picture background color g.clear (color.white);
/ / Draw picture background noise line for (int i = 0; i <25; i ) {INT x1 = random.next (image.width); int x2 = random.next (image.width); int y1 = random .Next (image.height); int y2 = random.next (image.height); g.drawline (new pen (color.silver), x1, y1, x2, y2);}
Font font = new System.Drawing.Font ( "Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic)); System.Drawing.Drawing2D.LinearGradientBrush 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);
前 图片 点 点 (int = 0; i <100; i ) {INT x = random.next (image.width); int y = random.next (image.height);
Image.setpixel (x, y, color.fromargb (random.next ()));}
// Draw the edge of the picture G.drawRectangle (New Pen (Color.Silver), 0, 0, Image.Width - 1, Image.Height - 1);
System.IO.MemoryStream ms = new System.IO.MemoryStream (); image.Save (ms, System.Drawing.Imaging.ImageFormat.Gif); Response.ClearContent (); Response.ContentType = "image / Gif"; Response .Binarywrite (ms.toarray ());} finally {g.dispose (); image.dispose ();}}}
If the above verification code generator page name is: checkcode.aspx, then "" in the login page to display the generated verification code picture:
in the login page Use the following code to determine the verification code in the processing event of the login button:
Private void btnlogin_click (object sender, system.web.ui.ImageClickeventargs e) {if (request.cookies ["checkcode"] == null) {lblMessage.Text = "Your browser setting has been disabled, you must set The browser allows you to use the cookies option to use this system. "; LblMessage.visible = true; return;
IF (String.Compare (Request.Cookies ["Checkcode"]. Value, txtcheckcode.text, true)! = 0) {lblMessage.Text = "Verification code error, please enter the correct verification code."; lblMessage.visible = True; return;} / ***** Other code ***** /} renderings:
You can use or part to reference this code, but you must retain the content of the above copyright annotation, and note the source of the code, otherwise the right to investigate the violations will be retained!
