All about PHP/MySQL

Remove Common Words from Search String

2009-02-07T00:43:00.000-08:00

Before sending the user given search string to MySql, its a good idea to remove common words used in it so that it may not disturb any relevant results you have in your DB. Their are far more professional approaches out there for this task but here I am mentioning a very simple one.

Function:

function RemoveCommonWords($sText){
$CommonWords = array (
'at',
'the',
'and',
'of',
'in'
);
for ($x = 0; $x < count($CommonWords); $x++) {
$sText = str_replace(' ' . $CommonWords[$x] . ' ', ' ', $sText);
}
return $sText;
}

Usage:

$search_string = "sports shops in market";

$search_string = RemoveCommonWords($search_string);

Build your own list in the function against the variable $CommonWords.

Good Luck :)

PHP function for Basic Image Gallery

2009-02-07T00:01:00.001-08:00

This PHP function is a very basic one, yet useful for a single page image gallery within a small website. It reads all the images from given folder and creates a simple looking gallery with given sized thumbnails.

Function:

function Create_Gallery($dir, $width, $height){

$folder=dir($dir);

$gallery_html = '<div> ';

while($folderEntry=$folder->read())
{
if ($folderEntry != "." && $folderEntry != ".."){
$gallery_html .= ' <a href="'.$dir.'/'.$folderEntry.'"> <img style="border: 6px double rgb(84, 85, 101);" src="'.$dir.'/'.$folderEntry.'" alt="The thumb" width="'.$width.'" height="'.$height.'"/></a>';
}
}

$gallery_html .= ' </div> ';
$folder->close();

echo $gallery_html;

return;
}

Usage:

Create_Gallery("gallery_images", "200", "140");

Where 'gallery_images' is the folder containing the images. 2nd and 3rd arguments of the function are the desired width and height of thumbnails.

Good Luck :)

Putting watermark on an Image

2009-02-06T00:25:00.001-08:00

While working on a project, I found this useful class for achieving watermarking task easily. Here is the code.

Class:

class watermark
{
var $img;
function create_watermark( $main_img_obj, $watermark_img_obj, $alpha_level = 100 )
{
$alpha_level /= 100;
$main_img_obj_w = imagesx( $main_img_obj );
$main_img_obj_h = imagesy( $main_img_obj );
$watermark_img_obj_w = imagesx( $watermark_img_obj );
$watermark_img_obj_h = imagesy( $watermark_img_obj );
$main_img_obj_min_x=10;
$main_img_obj_max_x=10;
$main_img_obj_min_y=10;
$main_img_obj_max_y=10;
$return_img = imagecreatetruecolor( $main_img_obj_w, $main_img_obj_h );

for( $y = 0; $y < $main_img_obj_h; $y++ )
{
for( $x = 0; $x < $main_img_obj_w; $x++ )
{
$return_color = NULL;
$watermark_x = $x - $main_img_obj_min_x;
$watermark_y = $y - $main_img_obj_min_y;
$main_rgb = imagecolorsforindex( $main_img_obj,
imagecolorat( $main_img_obj, $x, $y ) );
if ($watermark_x >= 0 && $watermark_x < $watermark_img_obj_w && $watermark_y >= 0 && $watermark_y < $watermark_img_obj_h )
{
$watermark_rbg = imagecolorsforindex( $watermark_img_obj,
imagecolorat( $watermark_img_obj, $watermark_x, $watermark_y ) );
$watermark_alpha = round( ( ( 127 - $watermark_rbg['alpha'] ) / 127 ), 2 );
$watermark_alpha = $watermark_alpha * $alpha_level;
$avg_red = $this->_get_ave_color( $main_rgb['red'],
$watermark_rbg['red'], $watermark_alpha );
$avg_green = $this->_get_ave_color( $main_rgb['green'],
$watermark_rbg['green'], $watermark_alpha );
$avg_blue = $this->_get_ave_color( $main_rgb['blue'],
$watermark_rbg['blue'], $watermark_alpha );
$return_color = $this->_get_image_color( $return_img, $avg_red, $avg_green, $avg_blue );
}
else
{
$return_color = imagecolorat( $main_img_obj, $x, $y );
}
imagesetpixel( $return_img, $x, $y, $return_color );
}
}
$this->img = $return_img;
}
function _get_ave_color( $color_a, $color_b, $alpha_level )
{
return round((($color_a*(1-$alpha_level))+($color_b*$alpha_level)));
}
function _get_image_color($im, $r, $g, $b)
{
$c=imagecolorexact($im, $r, $g, $b);
if ($c!=-1)
{
return $c;
}
$c=imagecolorallocate($im, $r, $g, $b);
if ($c!=-1)
{
return $c;
}
return imagecolorclosest($im, $r, $g, $b);
}
function write($target)
{
imagejpeg($this->img, $target, 100);
}
}

Usage:

$watermark = new watermark();
$main_img_obj = imagecreatefromjpeg("image.jpg"); //Image which you want to put watermark on
$watermark_img_obj = imagecreatefrompng("logo.png"); //Watermark image (PNG file)
$watermark->create_watermark( $main_img_obj, $watermark_img_obj, 100 );
$watermark->write("image_with_watermark.jpg"); //Output Image

It takes image.jpg, puts logo.png on it as watermark and saves it as a new image file named image_with_watermark.jpg. Thats it!

Happy Coding :)

Calculating Age from Date of Birth

2009-02-05T23:49:00.000-08:00

In some sections (e.g Profile pages) its nice to display the user's age for the page viewers. Its easier with the following function to calculate age by providing a valid date of birth.

Function:

function GetAge($DOB) {

list($Year, $Month, $Day) = explode("-",$DOB);
$YearDifference = date("Y") - $Year;
$MonthDifference = date("m") - $Month;
$DayDifference = date("d") - $Day;

if ($DayDifference < 0 || $MonthDifference < 0) {
$YearDifference--;
}

return $YearDifference;

}

Usage:

$age = GetAge("1981-05-18"); //Year-Month-Day

echo $age;

Happy Coding :)

Fetch a URL (with cURL)

2009-02-05T23:35:00.000-08:00

cURL is a very useful PHP library which can be used to connect to different types of servers with different types of protocols. Here is a very basic example of its primary usage.

function fetchPage($url)
{

$ch = curl_init($url);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$responce = curl_exec($ch);
curl_close ($ch);

$data =$responce;

return $data;

}

$page_data = fetchpage("www.cnn.com");

echo $page_data;

You can do the magic by using Regular Expressions on the data stored in $page_data variable.

See this post of my kind friend Mr. Siddique Ahmed on crawling guide using Simple Html DOM Class.

Happy Coding :)

Clean An Email Address

2009-02-05T23:23:00.001-08:00

Use this function to cleanup an email address. It will remove any unwanted character smoothly.

Function:

function clean_email($email = "")
{
$email = trim($email);
$email = str_replace(" ", "", $email);

// Check for more than one @
if (substr_count($email, '@') > 1)
{
return false;
}

$email = preg_replace("#[\;\#\n\r\*\'\"<>&\%\!\{\}\[\]\?\\/\s]#", "", $email);

if (preg_match("/^.+\@(\[?)[a-zA-Z0-9\-\.]+\.([a-zA-Z]{2,4}|[0-9]{1,4})(\]?)$/", $email))
{
return $email;
}
else
{
return false;
}
}

Usage:

$email_address = clean_email("my!email@domain.com");

It will save "myemail@domain.com" after removing the typo mistake (probably) by user.

Happy Coding :)

Graphical Bar for Percentage Values

2009-02-05T22:59:00.000-08:00

Following function can be used to display the percentage value (e.g Polling Result) in form of graphical bar.

Function:

function DrawBar($percentage) {
if ($percentage > 0)
{
$per = imagecreate($percentage * 3,20);
$background = imagecolorallocate($per, 0x00, 0x99, 0xFF);
$foreground = imagecolorallocate($per, 0x00, 0x8A, 0x01);
$border = imagecolorallocate($per, 0x99, 0x99, 0x99);

header("Content-type: image/png");
imagepng($per);
imagedestroy($per);
}else{
$per = imagecreate(2,20);
$background = imagecolorallocate($per, 0x00, 0x99, 0xFF);
$foreground = imagecolorallocate($per, 0x00, 0x8A, 0x01);
$border = imagecolorallocate($per, 0x99, 0x99, 0x99);

header("Content-type: image/png");
imagepng($per);
imagedestroy($per);
}
}

Usage:

DrawBar($_GET['value']);

$_GET['value'] is the percentage value which we want the function to display in graphical format. You can use this script in <img> tag also. Create a file named as graph.php and save the above code in it. Then in html portion you can call the script in the following way:

<img src="graph.php?value=75">

<img src="graph.php?value=65">

Easy and Useful!

Happy Coding :)

Function to resize images in PHP

2008-03-14T02:50:00.001-07:00

Very easy and useful function to resize images (of png,gif and jpg extensions) in php. I do use it often in my scripts to make the task easier.

function Resize_File($file, $directory, $max_width = 0, $max_height = 0)
{
global $config;

$full_file = $directory.$file;

if (eregi("\.png$", $full_file))
{
$img = imagecreatefrompng($full_file);
}

if (eregi("\.(jpg|jpeg)$", $full_file))
{
$img = imagecreatefromjpeg($full_file);
}

if (eregi("\.gif$", $full_file))
{
$img = imagecreatefromgif($full_file);
}

$FullImage_width = imagesx($img);
$FullImage_height = imagesy($img);

if (isset($max_width) && isset($max_height) && $max_width != 0 && $max_height != 0)
{
$new_width = $max_width;
$new_height = $max_height;
}
elseif (isset($max_width) && $max_width != 0)
{
$new_width = $max_width;
$new_height = ((int)($new_width * $FullImage_height) / $FullImage_width);
}
elseif (isset($max_height) && $max_height != 0)
{
$new_height = $max_height;
$new_width = ((int)($new_height * $FullImage_width) / $FullImage_height);
}
else
{
$new_height = $FullImage_height;
$new_width = $FullImage_width;
}

$full_id = imagecreatetruecolor($new_width, $new_height);
imagecopyresampled($full_id, $img, 0, 0, 0, 0, $new_width, $new_height, $FullImage_width, $FullImage_height);

if (eregi("\.(jpg|jpeg)$", $full_file))
{
$full = imagejpeg($full_id, $full_file, 100);
}

if (eregi("\.png$", $full_file))
{
$full = imagepng($full_id, $full_file);
}

if (eregi("\.gif$", $full_file))
{
$full = imagegif($full_id, $full_file);
}

imagedestroy($full_id);
unset($max_width);
unset($max_height);
}

Usage:
Below is a little example of its usage.

Resize_File("original.jpg", 'images/', 100, 75);

It will set the size of 'original.jpg', which exists in 'images' folder, to 100x75.

Happy coding :-)

Create nested (dynamic) table

2008-03-13T08:19:00.000-07:00

In a project where i was calling the data from a mysql table, the requirement came to place it in a html table with a specific number of columns in it. Code should break the row after 3 columns (for example) and a new row of table should start after that. I wrote the following function to accomplish this task. I hope you will find it useful for your scripts.

<?php
function DrawTable($data,$total,$col)
{
$end = '0';
$newrowcount = '0';
?>
<table border="1" cellspacing="1" width="100%" id="AutoNumber1">
<?php while ($row = mysql_fetch_array($data)){
if ($newrowcount == $col)
{
$newrowcount = 0;
echo "<tr>";
}
?>

<td><?php echo $row['Name']; ?></td>
<?php $newrowcount++;
if ($newrowcount == $col) {echo"</tr>";}

$end = $end + 1;
} ?>
</table>
<?php
return true;
}
?>

Usage:
In my example, I have a table named as 'country' having the countries of world. I will display them in html table with a sequence of 3 columns in a row. Lets start the code.

<?php
include "db.php";
$result = mysql_query("select * from country order by Name") or die(mysql_error());
$total = mysql_num_rows($result);
DrawTable($result,$total,3);
?>

As you noticed, I included the db file, executed the query and got its result and the total number of records it has. Then i passed the three arguments to the function. First is the record set, second is the total number of records and the third is the number of columns I want to create in a single row. Then I displayed the country name in the function among the <td> and </td> tags. You can do your own experiments up there as this is just one example of how it can be. And of course you can easily format the html table according to your specific page layout. Possibilities are endless.

If you have any question or want explanation then kindly post the comment and I will try to reply in minimum time.

Thanks

Happy Coding :-)

Random string generator in PHP

2008-02-27T09:49:00.001-08:00

In many cases, like generating a new password or setting up the custom session id, i do use the following function often in my PHP scripts for random string generation:

Function:

function random_string($length='8')
{
$ran_string = "";
$chars = array("1", "2", "3", "4", "5", "6", "7", "8", "9", "0", "a", "A", "b", "B", "c",

"C", "d", "D", "e", "E", "f", "F", "g", "G", "h", "H", "i", "I", "j", "J", "k", "K", "l",

"L", "m", "M", "n", "N", "o", "O", "p", "P", "q", "Q", "r", "R", "s", "S", "t", "T", "u",

"U", "v", "V", "w", "W", "x", "X", "y", "Y", "z", "Z");

$count = count($chars) - 1;

srand((double)microtime() * 1000000);

for ($i = 0; $i < $length; $i++)
{
$ran_string .= $chars[rand(0, $count)];
}

return($ran_string);
}

Usage:

$new_random_string = random_string();

Happy coding :-)

function for SQL Injection Protection

2008-02-27T09:26:00.000-08:00

If you are using the web forms on your website to collect some user based data to put into a database then this function is right there for you to avoid any SQL injection injected by an experienced hacker. Without going into the details of hacking stuff i am putting the function here to enhance the site's security:

function quote_smart($value)
{
if (get_magic_quotes_gpc())
{
$value = stripslashes($value);
}

if (!is_numeric($value))
{
$value = "" . mysql_real_escape_string($value) . "";
}
return $value;
}

Simply scan the posted data before inserting it into database table. For example:

$form_field_value = quote_smart($_POST['form_field_name']);

This would help a lot am sure.

Happy coding :-)

Solution of a common error - Headers already sent!!

2008-02-26T08:16:00.000-08:00

Since the beginning (not too long), while working on many php scripts i faced the 'Headers already sent' error many times and i was realy got stucked with that. I passed many hours on google and visited lot of forum posts but wasnt able to detect any quick solution. Some were saying to remove the blank spaces before starting of php tag and some where enforcing to do some other checks around the scripting files. Ofcourse the solutions worked for sometime but they were really time taking. Then a friend of mine, Rajneesh from india, suggested me to use a php function ob_start() while i was again stucked with same error in a script and deadline of that project was almost there. Here is the official definition i could get from php.net regarding this really useful function.

'' This function will turn output buffering on. While output buffering is active no output is sent from the script (other than headers), instead the output is stored in an internal buffer.''

This solved my problem for ever! Here is the method of its implementation.

Write down the ob_start() in very beginning of the script like:

<?php
ob_start();

And add this at the end:

ob_end_flush();
?>

And thats it. You will no more receive the 'Headers already sent' error ever on that script even if your script is sending the headers before any output.

I hope this solution will help someone else too facing same problem with PHP.