Category: PHP

I recently did some work for a small local non-profit group to accept payment over PayPal. They have multiple, but limited, offerings that they were selling to raise funds, and customers could purchase in variable quantities. They originally used the buttons auto-generated by PayPal, but that functionality forces their customers to go back and forth between the single-page sales page and the PayPal shopping cart, which creates too much complexity for their simple sales process. Below is a simplified version of what I put together for them.

First, this is the sales form:

	<form method="post">
		<table border="0">
			<tr><td>Name</td><td>&nbsp;</td><td><input type="text" name="name" id="name" maxlength="100" /></td></tr>
			<tr><td>Email</td><td>&nbsp;</td><td><input type="text" name="email" id="email" maxlength="100" /></td></tr>
			<tr><td>Phone</td><td>&nbsp;</td><td><input type="text" name="phone" id="phone" maxlength="100" /></td></tr>
			<tr><td colspan="9"><br />I wish to purchase:<br /><br /></td></tr>
			<tr><td>Product 1</td><td>&nbsp;</td><td><select name="prod1"><option value="0">0</option><option value="1">1</option><option value="2">2</option><option value="3">3</option><option value="4">4</option><option value="5">5</option><option value="6">6</option><option value="7">7</option><option value="8">8</option><option value="9">9</option><option value="10">10</option><option value="11">11</option><option value="12">12</option></select> @ $5 ea.</td></tr>
			<tr><td>Product 2</td><td>&nbsp;</td><td><select name="prod2"><option value="0">0</option><option value="1">1</option><option value="2">2</option><option value="3">3</option><option value="4">4</option><option value="5">5</option><option value="6">6</option><option value="7">7</option><option value="8">8</option><option value="9">9</option><option value="10">10</option><option value="11">11</option><option value="12">12</option></select> @ $5 ea.</td></tr>
			<tr><td>Product 3</td><td>&nbsp;</td><td><select name="prod3"><option value="0">0</option><option value="1">1</option><option value="2">2</option><option value="3">3</option><option value="4">4</option><option value="5">5</option><option value="6">6</option><option value="7">7</option><option value="8">8</option><option value="9">9</option><option value="10">10</option><option value="11">11</option><option value="12">12</option></select> @ $10 ea.</td></tr>
			<tr><td>Product 4</td><td>&nbsp;</td><td><select name="prod4"><option value="0">0</option><option value="1">1</option><option value="2">2</option><option value="3">3</option><option value="4">4</option><option value="5">5</option><option value="6">6</option><option value="7">7</option><option value="8">8</option><option value="9">9</option><option value="10">10</option><option value="11">11</option><option value="12">12</option></select> @ $20 ea.</td></tr>
		</table>
		<input type="submit" value="Review Order" />
	</form>

The next page grabs the values passed in from the previous page and displays a confirmation screen for the customer to review; if all looks ok, the customer will submit the following form. Note the specific form action and hidden inputs (cmd, upload, business, and currency_code) required by PayPal. Multiple products is achieved by creating sets of inputs (item_name_*, quantity_*, amount_*) for each product, with the asterisk being a number; the numbering must start from 1 and subsequent products must be in order, ie. 2, 3, 4, etc., thus the use of the IF statements and the $itemCnt counter variable. The amount_* field represents the unit price of the associated product, not the line total.

	<form action="https://www.paypal.com/cgi-bin/webscr" method="post">
		<input type="hidden" name="cmd" value="_cart">
		<input type="hidden" name="upload" value="1">
		<input type="hidden" name="business" value="store@email.here">
		<input type="hidden" name="currency_code" value="USD">
		<?php
		$itemCnt = 1;
		if ($prod1 != "0") {
			?>
			<input type="hidden" name="item_name_<?php print($itemCnt); ?>" value="Product 1">
			<input type="hidden" name="quantity_<?php print($itemCnt); ?>" value="<?php print($prod1); ?>">
			<input type="hidden" name="amount_<?php print($itemCnt); ?>" value="5">
			<?php
			$itemCnt++;
		}
		if ($prod2 != "0") {
			?>
			<input type="hidden" name="item_name_<?php print($itemCnt); ?>" value="Product 2">
			<input type="hidden" name="quantity_<?php print($itemCnt); ?>" value="<?php print($prod2); ?>">
			<input type="hidden" name="amount_<?php print($itemCnt); ?>" value="5">
			<?php
			$itemCnt++;
		}
		if ($prod3 != "0") {
			?>
			<input type="hidden" name="item_name_<?php print($itemCnt); ?>" value="Product 3">
			<input type="hidden" name="quantity_<?php print($itemCnt); ?>" value="<?php print($prod3); ?>">
			<input type="hidden" name="amount_<?php print($itemCnt); ?>" value="10">
			<?php
			$itemCnt++;
		}
		if ($prod4 != "0") {
			?>
			<input type="hidden" name="item_name_<?php print($itemCnt); ?>" value="Product 4">
			<input type="hidden" name="quantity_<?php print($itemCnt); ?>" value="<?php print($prod4); ?>">
			<input type="hidden" name="amount_<?php print($itemCnt); ?>" value="20">
			<?php
			$itemCnt++;
		}
		// Repeat as necessary...
		?>
	</form>

The PHP code below goes through a directory/folder recursively and display the files found as HTML links on a web page.

// Configuration
$cDrivePath = "C:\\inetpub\\site3\\filelibrary\\"; // Be sure to include slash at the end!
$webPath = "/filelibrary/"; // Be sure to include slash at the end!
// End configuration

function cleanUpFileName($fName, $removeThisString) {
	$ret = $fName;
	$ret = str_replace($removeThisString, "", $ret);
	$ret = str_replace("\\", " > ", $ret);
	return $ret;
}

function printDirContents(
		$path, 			// This is the HDD path to recurse into
		$cDrivePath, 	// Always carry the $cDrivePath value; used for beautifying text
		$webPath		// Always carry the $webPath value; used for beautifying text
	) {

	// Make sure we have a trailing slash and asterix
	$path = rtrim($path, "\\") . "\\*";

	// Make an array to hold all the sub-directories
	$dirs = glob($path, GLOB_ONLYDIR);
	
	// Make an array to hold all the files
	$files = glob($path); //This contains both sub-directories and files
	$files = array_diff($files, $dirs); // Remove sub-directories from the array
	
	// Print files
	foreach ($files as &$f) {
		$fnDownload = str_replace($cDrivePath, "", $f);
		$fnDisplay = cleanUpFileName($f, str_replace("*","",$path));
		print("[a href='".$webPath.$fnDownload."']".$fnDisplay."[/a]");
	}
	
	// Recurse into sub-directories
	foreach ($dirs as &$d) {
		print("[h3]".(cleanUpFileName($d, $cDrivePath))."[/h3]";
		// Print folder
		printDirContents($d, $cDrivePath, $webPath);
	}
}
$displayArray = printDirContents($cDrivePath, $cDrivePath, $webPath);

function twitterUpdate($u, $p, $upd) {
	// $u is your username (string)
	// $p is your password (string)
	// $upd is your status update (string)

	$url = 'http://twitter.com/statuses/update.xml';

	$curl_handle = curl_init();
	curl_setopt($curl_handle, CURLOPT_URL, $url);
	curl_setopt($curl_handle, CURLOPT_CONNECTTIMEOUT, 2);
	curl_setopt($curl_handle, CURLOPT_RETURNTRANSFER, 1);
	curl_setopt($curl_handle, CURLOPT_POST, 1);
	curl_setopt($curl_handle, CURLOPT_POSTFIELDS, "status=".$upd);
	curl_setopt($curl_handle, CURLOPT_USERPWD, $u.":".$p);
	$buffer = curl_exec($curl_handle);
	curl_close($curl_handle);

	if (empty($buffer)) {
		return 'fail';
	}
	else {
		return 'success';
	}
}

Example usage is below.

$u='username';
$p='password';
$upd='Hello world!';

$twitterUpdateResult = twitterUpdate($u, $p, $upd);

echo $twitterUpdateResult;

I was working on my World War II photo gallery recently. The gallery’s HTML code, particularly the main content section, looks something like the following.

<div id="content">
	<div class="main_column">
		<img decoding="async" src="images/helloWorld.jpg">
		<!--
		The photograph and other "main content" goes here.
		The width of this column is 600px.
		-->
	</div>

	<div class="extra_column">
		<!--
		This is the vertical side bar.
		If the width of the photo in the main section is more
		than 600px, it will overlap this div.
		-->
	</div>
</div>

Because my vertical navigation bar is on the right side of the page, if a photograph is larger than a particular width, it overlaps the vertical bar. I decided to remove the vertical bar if the photo is too large; let us assume that if the image width is larger than 580 pixels, it is too large. To apply the logic, I used the getimagesize() function. A quick example on this function is below.

list($imageWidth, $imageHeight, $imageType, $imageAttr) = getimagesize($imgName);
echo("The width of the image is ".$imageWidth." pixels.");
// Sample output: "The width of the image is 600 pixels."

I used the following PHP code to make my page work the way I want to based on width of the image.

<div id="content">
	<?php
	$imgName = "helloWorld.jpg";

	list($imageWidth, $imageHeight, $imageType, $imageAttr) = getimagesize($imgName);

	if ($imageWidth <= 580) { ?>
		<div class="main_column">
	<?php } ?>

	<img decoding="async" src="images/helloWorld.jpg">
	<!--
	The photograph and other "main content" goes here.
	-->

	<? if ($imageWidth <= 580) { ?>
		</div>
		<div class="extra_column">
		<!--
		This is the vertical side bar.
		Only show this if image width
		is 580 pixels or smaller.
		-->
		</div>
	<?php } ?>
</div>

Beyond width, the getimagesize() function in PHP also outputs other properties; the output is an array containing four elements. As you may have noticed, in my above example, I captured the following properties.

• 0 $imageWidth : Width of the image in pixels; integer.
• 1 $imageHeight : Height of the image in pixels; integer.
• 2 $imageType : Type of the image; integer. Possible values are as follows:
  

  Value	Description
  1	GIF
  2	JPG
  3	PNG
  4	SWF
  5	PSD
  6	BMP
  7	TIFF (Intel)
  8	TIFF (Motorola)
  9	JPC
  10	JP2
  11	JPX
  12	JB2
  13	SWC
  14	IFF
  15	WBMP
  16	XBM

• 3 $imageAttr : HTML-formatted attributes; string. Example: ‘height=”600″ width=”400″‘

In PHP, to output a line, we can use either the echo() or print() functions. All six examples below have the same output of “hello world”:

echo('hello world');
print('hello world');
print 'hello world';

echo("hello world");
print("hello world");
print "hello world";

Note the print() function can work without parenthesis. That is because print() is not really a function; print() is actually a language construct. Functions print() and echo() pretty much do the same thing, so generally you can use whichever one you prefer, though echo() actually gets processed faster, so if you are working with a larger application, this may be something to keep in mind.

To output a string variable, we can do something like this:

$name = "world";

echo('hello '.$name);
print('hello '.$name);
print 'hello '.$name;

echo("hello ".$name);
print("hello ".$name);
print "hello ".$name;

echo("hello $name");
print("hello $name");
print "hello $name";

Once again, all examples above output “hello world”, and the character used to concatenate the “hello” and the variable that contains “world” is the period character; the period is equivalent to the ampersand sign in VB/ASP and the plus sign in Java/JSP. Now, see the third set above where we used double quotes to enclose the string and the variable together. This is a special functionality you can use only with double quotes. It is a way to make your coding process slightly simpler, and the resulting code slightly easier to read, but keep in mind that this method makes the code run just a tad bit slower because when the PHP engine sees the double quote, it needs to be prepared to find and process variables — even if none are found.

In conclusion, echo() and print() are nearly identical, and the usage of double and single quotes are nearly identical, and you may choose whichever one that suits your style better. In terms of optimizing processing speed, however trivial, using echo() with single quote is preferred.