The method of simple generating verification code for ASP.

This paper describes the method of simple generation of verification code for ASP. Share to everyone for your reference, as follows:

1. Create a new generic handler

namespace webapplication1{//<summary>///$codebehindclassname $ for a summary description///</summary> [WebService ( Namespace = "http://tempuri.org/")] [webservicebinding (ConformsTo = wsiprofiles.basicprofile1_1)] public class Handler1:ihttphandler, irequiressessionstate {public void ProcessRequest (HttpContext context) {context.   Response.ContentType = "Image/gif";   Create Bitmap object, plot Bitmap basemap = new Bitmap (100, 30);   Graphics graph = graphics.fromimage (basemap); Graph.   FillRectangle (New SolidBrush (Color.White), 0, 0, 100, 30);   Font font = new Font (FONTFAMILY.GENERICSERIF, fontstyle.bold, GraphicsUnit.Pixel);   Random r = new Random ();   String letters = "ABCDEFGHIJKLMNPQRSTUVWXYZ";   String Letter;   StringBuilder s = new StringBuilder (); Add a random five letters for (int x = 0; x < 5; + +) {letter = letters. Substring (r.next (0, letters.    Length-1), 1);    S.append (letter); Graph.   DrawString (letter, font, New SolidBrush (Color.Black), X *, R.next (0, 8)); }//Confusing background   Pen Linepen = new Pen (new SolidBrush (Color.Black), 2); for (int x = 0; x < 6; × x + +) graph.   DrawLine (Linepen, New Point (R.next (0), R.next (0)), New Point (R.next (0,), R.next (0, 29)); Save the picture to the output stream basemap. Save (context.   Response.outputstream, imageformat.gif); Context. session["Checkcode"] = s.tostring (); If IRequiresSessionState is not implemented, there will be an error here, and the picture context cannot be generated.  Response.End ();   } public bool IsReusable {get {return false; }  } }}

2. Foreground code

It is hoped that this article will help you with ASP.