Thumbnail photo/image format .jpg, .gif, .png in PHP at the time of image upload

<?php
//define a maxim size for the uploaded images
define ("MAX_SIZE","2048");
// define the width and height for the thumbnail
// note that these dimensions are considered the maximum dimension and are not fixed,
// because we have to keep the image ratio intact or it will be deformed
define ("WIDTH","150");
define ("HEIGHT","100");

// this is the function that will create the thumbnail image from the uploaded image
// the resize will be done considering the width and height defined, but without deforming the image
function make_thumb($img_name,$filename,$new_w,$new_h)
{
//get image extension.
$ext=getExtension($img_name);
//creates the new image using the appropriate function from gd library
if(!strcmp("jpg",$ext) || !strcmp("jpeg",$ext))
$src_img=imagecreatefromjpeg($img_name);

if(!strcmp("png",$ext))
$src_img=imagecreatefrompng($img_name);

if(!strcmp("gif",$ext))
$src_img=imagecreatefromgif($img_name);

//gets the dimmensions of the image
$old_x=imageSX($src_img);
$old_y=imageSY($src_img);

// next we will calculate the new dimensions for the thumbnail image
// the next steps will be taken:
// 1. calculate the ratio by dividing the old dimensions with the new ones
// 2. if the ratio for the width is higher, the width will remain the one define in WIDTH variable
// and the height will be calculated so the image ratio will not change
// 3. otherwise we will use the height ratio for the image
// as a result, only one of the dimensions will be from the fixed ones
$ratio1=$old_x/$new_w;
$ratio2=$old_y/$new_h;
if($ratio1>$ratio2) {
$thumb_w=$new_w;
$thumb_h=$old_y/$ratio1;
}
else {
$thumb_h=$new_h;
$thumb_w=$old_x/$ratio2;
}

// we create a new image with the new dimensions
$dst_img=ImageCreateTrueColor($thumb_w,$thumb_h);

// resize the big image to the new created one
imagecopyresampled($dst_img,$src_img,0,0,0,0,$thumb_w,$thumb_h,$old_x,$old_y);

// output the created image to the file. Now we will have the thumbnail into the file named by $filename
if(!strcmp("png",$ext))
imagepng($dst_img,$filename);
else
imagejpeg($dst_img,$filename);

//destroys source and destination images.
imagedestroy($dst_img);
imagedestroy($src_img);
}

// This function reads the extension of the file.
// It is used to determine if the file is an image by checking the extension.
function getExtension($str) {
$i = strrpos($str,".");
if (!$i) { return ""; }
$l = strlen($str) - $i;
$ext = substr($str,$i+1,$l);
return $ext;
}

// This function upload the file.
function uploadimage($imagepath, $thumbpath){
$image=$_FILES['image']['name'];
if ($image)
{
// get the original name of the file from the clients machine
$filename = stripslashes($_FILES['image']['name']);
// get the extension of the file in a lower case format
$extension = getExtension($filename);
$extension = strtolower($extension);
// if it is not a known extension, we will suppose it is an error, print an error message
if (($extension != "jpg") && ($extension != "jpeg") && ($extension != "png")&& ($extension != "gif"))
{
echo '<h1>Unknown extension!</h1>';
$errors=1;
}
else
{
// get the size of the image in bytes
// $_FILES[\'image\'][\'tmp_name\'] is the temporary filename of the file in which the uploaded file was stored on the server
$size=getimagesize($_FILES['image']['tmp_name']);
$sizekb=filesize($_FILES['image']['tmp_name']);

//compare the size with the maxim size we defined and print error if bigger
if ($sizekb > MAX_SIZE*1024)
{
echo '<h1>You have exceeded the size limit!</h1>';
$errors=1;
}
//we will give an unique name, for example the time in unix time format
$image_name=time().'.'.$extension;
//the new name will be containing the full path where will be stored (images folder)
$newname=$imagepath."/".$image_name;
$copied = copy($_FILES['image']['tmp_name'], $newname);
//we verify if the image has been uploaded, and print error instead
if (!$copied)
{
echo '<h1>Copy unsuccessfull!</h1>';
$errors=1;
}
else
{
// the new thumbnail image will be placed in images/thumbs/ folder
$thumb_name=$thumbpath.'/thumb_'.$image_name;
// call the function that will create the thumbnail. The function will get as parameters
$thumb=make_thumb($newname,$thumb_name,WIDTH,HEIGHT);
}
}
}
}

// checks if the form has been submitted
if(isset($_POST['Submit']) && !$errors )
{
uploadimage('images', 'images/thumbs');
echo "<h1>Thumbnail created Successfully!</h1>";
}

?>

<form name="newad" method="post" enctype="multipart/form-data" action="">
<div><label>Image: </label><input type="file" name="image" ></div>
<input name="Submit" type="submit" value="Upload image">
</form>

Access method of MySql used in PHP

<?php
/* do a MySQL query */
function do_query ($query, $db_link) {

$result = @mysql_query($query, $db_link);
if (!$result) {
fatal_error("A database query error has occurred!");
} else {
return($result);
}

}

/* get single result value */
function query2result ($query, $db_link) {

$result = do_query($query, $db_link);
$row = @mysql_result($result, 0);
return($row);

}

/* get result in numeric array */
function query2array ($query, $db_link) {

$result = do_query($query, $db_link);
$row = @mysql_fetch_row($result);
return($row);

}

/* get result in associative array */
function query2hash ($query, $db_link) {

$result = do_query($query, $db_link);
$row = @mysql_fetch_array($result);
return($row);

}

/* get row of result */
function result2row ($result) {

$row = @mysql_fetch_row($result);
return($row);

}

/* get row of result in hash */
function result2hash ($result) {

$row = @mysql_fetch_array($result);
return($row);

}

/* find number of rows in query result */
function number_rows ($result) {

$number_rows = @mysql_num_rows($result);
return($number_rows);

}

/* put rows from a column into an array */
function column2array ($query, $db_link) {

$result = do_query($query, $db_link);
while ($row = @mysql_fetch_array($result)) {
$array[] = $row[0];
}
return($array);

}
?>

rename() function renames a file or directory

<?php
rename("images","pictures");
?>

Parameter          Description
oldname          Required. Specifies the file or directory to be renamed
newname          Required. Specifies the new name of the file or directory
context          Optional. Specifies the context of the file handle. Context is a set of options that can modify the behavior of a stream

Backup Your MySQL Database Using PHP

<?php backup_tables('localhost','userid','password','dbname');


/* backup the db OR just a table */
function backup_tables($host,$user,$pass,$name,$tables = '*')
{

$link = mysql_connect($host,$user,$pass);
mysql_select_db($name,$link);

//get all of the tables
if($tables == '*')
{
$tables = array();
$result = mysql_query('SHOW TABLES');
while($row = mysql_fetch_row($result))
{
$tables[] = $row[0];

}
print_r($tables);
}

else
{
$tables = is_array($tables) ? $tables : explode(',',$tables);
}

//cycle through
foreach($tables as $table)
{
$result = mysql_query('SELECT * FROM '.$table);
$num_fields = mysql_num_fields($result);

$return.= 'DROP TABLE '.$table.';';
$row2 = mysql_fetch_row(mysql_query('SHOW CREATE TABLE '.$table));
$return.= "\n\n".$row2[1].";\n\n";

for ($i = 0; $i < $num_fields; $i++)
{
while($row = mysql_fetch_row($result))
{
$return.= 'INSERT INTO '.$table.' VALUES(';
for($j=0; $j<$num_fields; $j++)
{
$row[$j] = addslashes($row[$j]);
$row[$j] = ereg_replace("\n","\\n",$row[$j]);
if (isset($row[$j])) { $return.= '"'.$row[$j].'"' ; } else { $return.= '""'; }
if ($j<($num_fields-1)) { $return.= ','; }
}
$return.= ");\n";
}
}
$return.="\n\n\n";
}

//save file
$handle = fopen('db-backup-'.time().'-'.(md5(implode(',',$tables))).'.sql','w+');
fwrite($handle,$return);
fclose($handle);
}
?>

mysql_connect vs. mysql_pconnect

pconnects are expensive in RAM. Make sure you have enough to handle all the children you need and you're ok. total size of an average mysql child process, then subtract the amount of shared memory it uses and you have an approximate delta. Typical mysql is depending on the query you are running, are anywhere from 1 to 10 megs.

Displaying PHP SessionID

<?php
session_start();
?>
</HEAD>
<style type="text/css">
<!--
.style2 {color: #0066FF}
.style3 {
color: #009933;
font-weight: bold;
}
.style5 {color: #0066FF; font-weight: bold; }
-->
</style>
<BODY>
<strong>Displaying PHP SessionID by Tutorial Guide by http://www.phpmysqlquestion.blogspot.com/
</strong>
<h1 align="center" class="style2">Your PHPSESSID is: <?php echo session_id(); ?></h1>
<span class="style5">NOTE</span>: If you don't see a session id in tbe blue header above, hit <span

class="style3">REFRESH</span> on your browser <br />
<br />
<div align="center">Turotial by <a

href="http://www.phpmysqlquestion.blogspot.com/">http://www.phpmysqlquestion.blogspot.com/</a></div>
<p>
</BODY>
</HTML>

Difference between session-register and $_SESSION in PHP

Difference between session-register and $_SESSION in PHP

 

I read in the help http://www.php.net/session_register that using $_SESSION[var]=value is better than using session_register. It is because session_register() only works if register_globals is set ON in your php.ini file, but for security purposes this has been disabled by default since PHP 4.2.0 You should therefore use $_SESSION['var'] instead.