Website Verification Code Making

ASP. NET Verification Code production

Using System;

Using System.IO;

Using System.Drawing;

Using System.Drawing.Imaging;

Using System.Text;

Using System.Collections;

Using System.Web;

Using System.Web.UI;

Using System.Web.UI.WebControls;

Using System.Web.UI.WebControls.WebParts;

Using System.Web.UI.HtmlControls;

Namespace WebApplication1

{

public partial class Yzm:System.Web.UI.Page

{

protected void Page_Load (object sender, EventArgs e)

{

String Chkcode = String. Empty;

List of colors for verification codes, noise lines, noise points

color[] Color ={color.black, color.red, Color.Blue, Color.green, Color.orange, Color.brown, Color.brown, Color.DarkBlue };

Font list, for verification code

string[] Font ={"Times New Roman", "MS Mincho", "Book Antiqua", "Gungsuh", "PMingLiU", "Impact"};

The character set of the captcha, removing some easily confusing characters

char[] character ={' 2 ', ' 3 ', ' 4 ', ' 5 ', ' 6 ', ' 8 ', ' 9 ', ' A ', ' B ', ' C ', ' D ', ' E ', ' F ', ' G ', ' H ', ' J ', ' K ', ' L ', ' M ', ' N ', ' P ', ' R ', ' S ', ' T ', ' W ', ' X ', ' Y '};

Random rnd = new Random ();

Generate Authenticode String

for (int i = 0; i < 4; i++)

{

Chkcode + = Character[rnd. Next (character. Length)];

}

Store verification code with session object

session["name"] = Chkcode;

Bitmap bmp = new Bitmap (100, 40);

Graphics g = graphics.fromimage (BMP);

G.clear (Color.White);

Draw Noise Line

for (int i = 0; i <; i++)

{

int x1 = rnd. Next (100);

int y1 = rnd. Next (40);

int x2 = rnd. Next (100);

int y2 = rnd. Next (40);

Color clr = color[rnd. Next (color. Length)];

G.drawline (new Pen (CLR), x1, y1, x2, y2);

}

Draw a CAPTCHA string

for (int i = 0; i < chkcode.length; i++)

{

String fnt = Font[rnd. Next (font. Length)];

Font ft = new Font (FNT, 18);

Color clr = color[rnd. Next (color. Length)];

g.DrawString (Chkcode[i]. ToString (), FT, new SolidBrush (CLR), (float) I * 8, (float) 8);

}

Draw Noise points

for (int i = 0; i <; i++)

{

int x = rnd. Next (BMP. Width);

int y = rnd. Next (BMP. Height);

Color clr = color[rnd. Next (color. Length)];

Bmp. SetPixel (x, Y, CLR);

}

Clear the page output cache, set the page without caching

Response.Buffer = true;

Response.ExpiresAbsolute = System.DateTime.Now.AddMilliseconds (0);

Response.Expires = 0;

Response.CacheControl = "No-cache";

Response.appendheader ("Pragma", "No-cache");

Writes a CAPTCHA picture to the memory stream and outputs it in "image/png" format

MemoryStream ms = new MemoryStream ();

Try

{

Bmp. Save (MS, Imageformat.png);

Response.clearcontent ();

Response.ContentType = "Image/png";

Response.BinaryWrite (Ms. ToArray ());

}

Finally

{

Explicitly releasing resources

Bmp. Dispose ();

G.dispose ();

}

}

}

}

Website Verification Code Making