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B&T's Tips & Scripts is a collection of Tips & Scripts to help you build a better website. The Tips & Scripts are targeted towards the native Apache PHP MySQL environment. Check back frequently as there will be additions and modifications. Please check our terms of use.
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Using .htaccess 
- .htaccess Basics Mar 9, 2006
- Domain & subdomain pointing May 12, 2005
- Automatic subdomains Jun 17, 2007
- Undefined subdomains Jul 20, 2008
- Prevent direct access to a pointer or subdomain directory Aug 15, 2006
- Forcing or eliminating the WWW. Feb 9, 2005
- Fixing the trailing slash problem May 11, 2005
- Friendly URLs Mar 21, 2007
- Rewrites and https Dec 18, 2007
- Blocking traffic to your website Jan 2, 2005
- Anti-leech May 25, 2005
- Fancy default index page Jan 25, 2005
Using .htaccess/.htpasswd Password Protection 
- Setting up password protection Feb 9, 2005
- Encrypt your password for .htpasswd Dec 21, 2007
- Auto Password Change and Email Notification Dec 21, 2007
php5 - Auto generate .htpasswd file Dec 18, 2007 php5
- Passing user authentication information to PHP Jun 13, 2004
Coding Tips 
- HTML "One Liners" Nov 13, 2005
- PHP "One Liners" Apr 5, 2007
- JavaScript "One Liners" Aug 25, 2007
- CSS examples Sep 9, 2006
- SQL coding examples Aug 29, 2006
- AJAX example Sep 24, 2006
Uploads and Downloads 
- File Upload Script Dec 20, 2007 php5
- Custom Download Page Dec 14, 2007 php5
- Tracking and Securing Downloads Dec 20, 2007 php5
Mail 
- Form Mail Aug 19, 2007
- Obfuscate your email address Nov 12, 2006
- Read and auto-process mail Nov 12, 2004
- Auto-responder Dec 18, 2007 php5
- Display your email message count Jul 30, 2004
- Setting up SPF Records Jan 4, 2007
- Specify a return-path for generated mail Jul 18, 2006
Working with Images 
- Watermark images Jul 14, 2007
- Resize images (create thumbnails) Jul 14, 2007
Frequently Requested Website Functionality 
- Visitor Counter Dec 14, 2007 php5
- 404 Error Page (with reporting and logging) Dec 20, 2007 php5
- CAPTCHA Aug 19, 2006
- Poll (voting) Dec 17, 2007 php5 see it on this page
- Weather Jul 27, 2008 php5
- FAQ Page May 23, 2005
- Random/weighted banners, quotes & more Feb 9, 2005
- Load a random image (simple) Jan 20, 2004
- Image (banner) rotation Oct 15, 2007
- Simple "members only" pages May 13, 2005
- Replace banned words Apr 5, 2007
- Get the most recent file date Jan 30, 2006
- Moving (bouncing) Image Nov 10, 2005
- Sticky default values for an input Oct 22, 2006
Using PHP 
- Creating a custom php.ini file Dec 18, 2007 php5
- Copying the php.ini file Dec 18, 2007 php5
- Deleteing php.ini files Dec 18, 2007 php5
- Clean up your PHP scripts Nov 11, 2005
- Regular Expression Rules Mar 22, 2006
Website Managment 
- Tips for keeping your website secure Jan 24, 2006
- Using Cron Sep 13, 2005
- Website Monitoring Dec 19, 2007
- Automated Site Backups Dec 19, 2007
- Automated MySQL Backups Dec 19, 2007
- Server-to-server file transfer December 16, 2006
- MySQL Error Notification Dec 20, 2007
- Find File and Directory Sizes Dec 14, 2007 php5
- Deleting session files Aug 9, 2006
- FTP made easy Mar 1, 2006
- Search and Replace Dec 14, 2007 php5
Other Tips 
- URL Validation Feb 8, 2008
- Stop direct links to web pages Jan 22, 2004
- Ensure your page is not opened in a frame May 5, 2005
- Masking your URL in the Address Bar Jul 20, 2004
- Ban or allow IP Addresses (without using .htaccess) Jan 19, 20008
- Using Cookies Sep 24, 2006
- View your website in different resolutions Jan 2, 2005
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CAPTCHA
A CAPTCHA (an acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart", trademarked by Carnegie Mellon University) is a type of challenge-response test used in computing to determine whether or not the user is human.This CAPTCHA script presents a distorted image with six letters. It is relatively easy for a human to see the letters and enter them into a response box on your input form. Then you send the response back to the script for verification.
In your html form, put an <img> tag for the image and an input box, as in the example below. Do not put width or height parameters in the img tag as this will distort the generated image.
<img src="captcha.php" alt="captcha image missing" title="" />
<br />Please enter the letters in the box below<br />
<input type='text' name='captcha' style='width: 60px;' autocomplete='off' />
Then in your processing script you include the CAPTCHA script as in the example below:
$validate = $_POST['captcha'];
include('captcha.php');
if ($validate != "valid") $alert = "Wrong verification code entered";
Name the script below captcha.php.
You can download this script as a .txt file. Remember to rename the file as a .php file.
- - Start Script Here - -
<?php
//
// to validate the user entered value the variable $validate must be populated with the user input
// $validate will return with either "valid" or "invalid"
// if $validate is not set then a captcha image is generated
//
// to make the captcha harder for a bot to read, the font is random for each character and there are lines in the image
session_start();
// make the character array
$chars = array();
for ($i = 65; $i <= 90; $i++) $chars[] = chr($i);
if (isset($validate)) {
// this section validates the user input
if (strlen($validate) == 6) {
$validate = strtoupper($validate); // make input upper case for compare
if ($_SESSION['captcha'] == $validate) $validate = "valid"; else $validate = "invalid";
} else $validate = "invalid";
unset($_SESSION['captcha']);
} else {
// this section generated the captcha image
// generate values
for ($i = 1; $i <= 6; $i++) { $key = rand(0, count($chars)-1); $text[$i] = $chars[$key]; }
$_SESSION['captcha'] = $text[1] . $text[2] . $text[3] . $text[4] . $text[5] . $text[6];
// create image
$im = @imagecreate(70,25);
$backgroundColor = imagecolorallocate($im,150,150,150);
$textColor = imagecolorallocate($im,0,0,0);
$lineColor = imagecolorallocate($im,100,100,100);
imageline($im,0,0,23,25,$lineColor);
imageline($im,23,0,46,25,$lineColor);
imageline($im,46,0,69,25,$lineColor);
imageline($im,0,25,70,0,$lineColor);
imagestring($im, rand(3,5), 5, 5, $text[1], $textColor);
imagestring($im, rand(3,5), 15, 5, $text[2], $textColor);
imagestring($im, rand(3,5), 25, 5, $text[3], $textColor);
imagestring($im, rand(3,5), 36, 5, $text[4], $textColor);
imagestring($im, rand(3,5), 45, 5, $text[5], $textColor);
imagestring($im, rand(3,5), 55, 5, $text[6], $textColor);
imagepng($im);
imagedestroy($im);
}
?>
- - End Script Here - -
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