Create Page Turing.aspx
after the add captcha register.aspx page
using System;
using
System.Data;
using
System.Configuration;
using
System.Collections;
using
System.Web;
using
System.Web.Security;
using
System.Web.UI;
using
System.Web.UI.WebControls;
using
System.Web.UI.WebControls.WebParts;
using
System.Web.UI.HtmlControls;
using
System.Drawing.Text;
using
System.Drawing;
using
System.Drawing.Drawing2D;
using
System.Drawing.Imaging;
using
System.Security.Cryptography;
using
System.Text;
namespace sunilcaptcha
{
public partial class Turing
: System.Web.UI.Page
{
private static byte[] randb =
new byte[4];
private static RNGCryptoServiceProvider
rand = new RNGCryptoServiceProvider();
private
FontFamily[] fonts = {
new
FontFamily("Times New Roman"),
new
FontFamily("Georgia"),
new
FontFamily("Arial"),
new
FontFamily("Comic Sans MS")
};
protected void Page_Load(object
sender, EventArgs e)
{
int width =
200;
int hieght =
80;
Random random = new Random();
int ImageNum =
RandomNumber(0, 8); // (1-max number of background
images)
// Load image
// Bitmap bitMapImage = new
System.Drawing.Bitmap(filename);
Bitmap bitMapImage = new Bitmap(width, hieght,
PixelFormat.Format32bppArgb);
Graphics g =
Graphics.FromImage(bitMapImage);
Color bc = Color.White;
// Get random
string from RandomString(int sizeOfString) method
string
textToWrite = RandomString(8);
Rectangle rect = new Rectangle(0, 0, width, hieght);
g.SmoothingMode = SmoothingMode.AntiAlias;
using
(SolidBrush b = new SolidBrush(bc))
{
g.FillRectangle(b, rect);
}
// Set up the
text font.
int emSize = (int)(width * 5 / textToWrite.Length);
FontFamily family =
fonts[Next(fonts.Length - 1)];
Font font = new Font(family, emSize);
// Adjust the
font size until the text fits within the image.
SizeF measured = new SizeF(0, 0);
SizeF workingSize = new SizeF(width, hieght);
while (emSize
> 2 &&
(measured =
g.MeasureString(textToWrite, font)).Width > workingSize.Width ||
measured.Height >
workingSize.Height)
{
font.Dispose();
font = new Font(family, emSize -= 2);
}
// Set up the
text format.
StringFormat format = new StringFormat();
format.Alignment =
StringAlignment.Center;
format.LineAlignment =
StringAlignment.Center;
// Create a path
using the text and warp it randomly.
GraphicsPath path = new GraphicsPath();
path.AddString(textToWrite,
font.FontFamily, (int)font.Style, font.Size,
rect, format);
// Set font
color to a color that is visible within background color
int bcR = Convert.ToInt32(bc.R);
// This prevents
font color from being near the bg color
int red =
Next(255), green = Next(255), blue = Next(255);
while (red >=
bcR && red - 20 <= bcR ||
red < bcR && red
+ 20 >= bcR)
{
red = Next(0, 255);
}
//red=26
green=237, blue=
SolidBrush sBrush = new SolidBrush(Color.FromArgb(0, 201, 87));
g.FillPath(sBrush, path);
// Iterate over
every pixel
double distort =
Next(5, 15) * (Next(10) == 1 ? 1 : -1);
// Copy the
image so that we're always using the original for source color
using (Bitmap
copy = (Bitmap)bitMapImage.Clone())
{
for (int y = 0; y < hieght; y++)
{
for (int x = 0; x < width; x++)
{
// Adds a simple
wave
int newX = (int)(x + (distort * Math.Sin(Math.PI * y / 84.0)));
int newY = (int)(y + (distort * Math.Cos(Math.PI * x / 44.0)));
if (newX <
0 || newX >= width) newX = 0;
if (newY <
0 || newY >= hieght) newY = 0;
bitMapImage.SetPixel(x, y,
copy.GetPixel(newX, newY));
}
}
}
Session["randomStr"] = textToWrite.ToLower(); //Encoding.UTF8.GetString(md5.ComputeHash(pass));
System.IO.MemoryStream mstr = new
System.IO.MemoryStream();
// Save the
image
bitMapImage.Save(mstr,
ImageFormat.Jpeg);
// Set the
content type
Response.ContentType = "image/png";
// Write image
Response.BinaryWrite((byte[])(mstr).ToArray());
//Clean
font.Dispose();
sBrush.Dispose();
g.Dispose();
bitMapImage.Dispose();
}
public string GetRandomPasswordUsingGUID(int length)
{
// Get the GUID
string guidResult
= System.Guid.NewGuid().ToString();
// Remove the
hyphens
guidResult =
guidResult.Replace("-", string.Empty);
// Return the
first length bytes
return
guidResult.Substring(0, length);
}
private int RandomNumber(int
min, int max)
{
Random random = new Random();
return
random.Next(min, max);
}
private string RandomString(int
size)
{
string s = "";
char[] chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".ToCharArray();
int index;
int lenght =
Next(8, 8);
for (int i = 0; i < lenght; i++)
{
index = Next(chars.Length -
1);
s +=
chars[index].ToString();
}
return s;
}
public int Next()
{
rand.GetBytes(randb);
int value = BitConverter.ToInt32(randb, 0);
if (value
< 0) value = -value;
return value;
}
///
/// Generates a random non-negative number less than or equal to max.
///
///
The maximum possible value.
public int Next(int max)
{
rand.GetBytes(randb);
int value = BitConverter.ToInt32(randb, 0);
value = value % (max + 1); // % calculates remainder
if (value
< 0) value = -value;
return value;
}
///
/// Generates a random non-negative number bigger than or equal to min and
less than or
/// equal to max.
///
///
The minimum possible value.
///
The maximum possible value.
public int Next(int min, int max)
{
int value =
Next(max - min) + min;
return value;
}
}
}
after the add captcha register.aspx page
<%@ Page Language="C#"
AutoEventWireup="true"
Codebehind="register.aspx.cs"
EnableEventValidation="false"
Inherits="register" %>
DOCTYPE html PUBLIC
"-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>captchatitle>
<script language="Javascript" type="text/javascript">
function
refreshSecuritylogin()
{
var
randomnumber=Math.floor(Math.random()*1001);
document.images["refreshImg2"].src = "Turing.aspx" + '?rand='
+ randomnumber; ;
}
script>
head>
<body >
<form id="form1"
runat="server"
method="post">
<table width="1000"
border="0"
align="center"
cellpadding="0"
cellspacing="0">
<tr>
<td align="left"
valign="middle">
<table style="width:
100%">
<tr>
<td width="33%"
align="left"
height="40"
valign="middle"
id="Code">
Security Codetd>
<td width="67%"
align="left"
valign="middle">
<asp:TextBox CssClass="text_field"
ID="txtSecurityCode"
runat="server"
TabIndex="13"
AutoCompleteType="None" MaxLength="8"
Style="width:
160px; height: 25px;">asp:TextBox>
<asp:LinkButton ID="lnkRefreshCode"
runat="server"
OnClick="lnkRefreshCode_Click"
TabIndex="40">
<asp:Label ID="lblRefreshCode"
runat="server"
Text="Refresh
Code" Visible="false" />
asp:LinkButton>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1"
runat="server"
ControlToValidate="txtSecurityCode"
ErrorMessage="Enter
Security Code" ValidationGroup="SignUPpop" Display="none">*asp:RequiredFieldValidator>
td>
tr>
<tr>
<td align="left"
valign="top">
td>
<td align="left"
valign="top">
<img src="Turing.aspx"
class="text_field"
alt="refreshImg"
name="refreshImg"
id="refreshImg" height="50px"
width="160px"/>
<br />
<a href="#"
onclick="return
refreshSecurity();" tabindex="14">Refresh Codea>
td>
tr>
table> td>
<td height="40" align="left" valign="middle">
<asp:ImageButton ID="imgbtnsubmit"
runat="server"
ValidationGroup="RegisterSignUP"
TabIndex="15" ImageUrl="images/register_2.png"
Width="62"
Height="28"
border="0"
OnClick="imgbtnsubmit_Click" OnClientClick="return
ShowModalDialog()" />
<asp:ImageButton ID="ImageButton1"
runat="server"
Width="49"
Height="28"
ImageUrl="images/reset.png"
alt="send" border="0" OnClick="ImageButton1_Click"
/>
td>
tr>
<tr>
<td align="left"
valign="middle">
td>
<td align="left"
valign="middle">
td>
tr>
table>
div>
div>
td>
tr>
<tr>
<td align="left"
valign="top">
td>
tr>
table>
td>
tr>
table>
form>
body>
html>
