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Manual Installation Tutorial for PHP 5 on IIS 5.1 (Windows XP Pro)

Sunday, February 14th, 2010

Prerequisite: IIS (web server) installed. There is a link to an IIS installation tutorial at the end of this article

Before we begin any installation steps, the first thing we will need to do is download the PHP zip file from PHP.net (www.php.net/downloads.php). The version available at the time of this publishing is 5.1.4.

The first step is to extract all of the files from the downloaded zip file into C:PHP (create the folder if it doesn’t already exist). You may choose a different location, although it is not recommended. The path must NOT have spaces, for example, you cannot use C:Program FilesPHP. Some web servers may not be able to handle the path name and will fault.

PHP 5 includes a CGI executable, a CLI executable as well as the server modules. The DLLs needed for these executables can be found in the root of the PHP folder (C:PHP).

php5ts.dll needs to be available to the web server. To do this, you have 3 options:

1. Copy php5ts.dll to the web server’s directory (C:inetpubwwwroot).

2. Copy php5ts.dll to the Windows system directory (C:windowssystem32).

3. Add the PHP directory path to the environment variables PATH.

We will go with option 3, because we would like to keep all of our PHP install files in the same location, for easier cleanup later, if needed. Let’s proceed…

Instructions on how to put C:php in env variables PATH.

First we want to open System Properties. There are two ways to get to System Properties. Either way will work.

1. Right-Click on My computer and choose “properties”.

2. Go to Control Panel, and select “System”.

Once here, we want to select the Advanced tab. In the Advanced tab, click the “Environment Variables” button. There are two sections in the Environment Variables window, User Variable and System Variables. We will be using System Variables. Scroll down in System Variables until you find the variable PATH. Highlight that line and the select Edit below the System Variables window. We will only be adding to the Variable Value. BE CAREFUL HERE. You do not want to delete anything on this line. Simply find the end of the line and add a semi-colon ( ; ) if there is not one already. After the semi-colon, type: C:PHP and then hit OK. Now click OK on the Environment Variables window. Finally click OK on the System Properties window and we are done with this part.

Now we must restart the computer to make the Environment Variables changes come into play. We cannot simply log off and log on, you must restart.

The next step is to set up a config file for PHP, php.ini. In C:PHP you will find two files named php.ini-dist and php.ini-recommended. We will use php.ini-recommended for this install, and all you need to do is rename it from php.ini-recommended to php.ini.

1. doc_root = C:inetpubwwwroot

2. cgi.force_redirect = 0

Now PHP is installed, lets move on to preparing our IIS to use PHP.


Configure IIS to use PHP.

1. Open IIS

2. Under Home Directory: Set “Execute Permissions” to “Scripts Only”

3. Click on configuration..

a. Click Add

b. Set “executable” to C:PHPphp5isapi.dll

c. Set “extension” to .php (don’t forget to include the . )

d. Click OK

e. Click Apply, then OK.

Under ISAPI Filters

a. Click “Add”

b. Set Filter Name to PHP

c. Set Executable to C:PHPphp5isapi.dll

d. Click OK.

e. Click Apply, then OK.

Restart the Web Server

Now we want to test PHP on our system. To do this, we will create a file called phpinfo.php and it will be used to display all of the PHP info from our system in our web browser.

1. Open Notepad and type:

2. Save the file as phpinfo.php and select the file type ‘All Files’(Important: do not save the file as .txt, as it will not work).

3. Move the file into C:inetpubwwwroot

4. Open your web browser and type: [http://localhost/phpnfo.php]

5. Your browser should display a lot of PHP information.
Click here for IIS installation tutorial. [http://www.studiothreehundred.com/viewarticle.php?id=45]

Congratulations! PHP is now installed and configured on your machine. You can now start building dynamic web pages.

Author: C Alexander
Provided by: Canada duty

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Benefits of PHP Programming

Thursday, December 3rd, 2009

PHP is a server-side programming language and it’s immensely utilised by software developers to construct dynamic web pages and to develop textual user interfaces. As a programming language it is vastly used in different segments while developing a professional website. With the help of PHP coding we can easily develop  money making websites.

Custom PHP programming can be applied in several areas in web development like

Back end Admin
Shopping Carts
Banner and advertising management
Web content management systems
Membership management systems
Blogs
Mailing systems
Visitor tracking
Feedback form
Forums and message boards

Some features of PHP

Ease of writing interfaces to other libraries.
PHP code is platform independent therefore can run on (just about) any platform.
Many types of database accessibility like MySQL, MS SQL, Oracle and so on.
PHP programming syntax is akin to C and C++ therefore easy understandable by computer programmers
PHP is an extensible language by nature.
PHP is Open Source.

Advantages of PHP

Fast, reliable, stable, easy to understand and high performance programming language.
Well-matched with varied servers like IIS and Apache.
PHP may be executed on any major operating systems like Windows, Linux and Unix etc.
PHP programming can be utilised in a big number of relational DBMSs such as MySQL and PostgreSQL.
It offers flexibleness during and after the initial project to PHP programmers.
PHP supplies quick execution of complex application solutions.

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Optimizing your php code

Monday, June 8th, 2009

1. If a method can be static, declare it static. Speed improvement is by a factor of 4.

2. echo is faster than print.

3. Use echo’s multiple parameters instead of string concatenation.

4. Set the maxvalue for your for-loops before and not in the loop.

5. Unset your variables to free memory, especially large arrays.

6. Avoid magic like __get, __set, __autoload

7. require_once() is expensive

8. Use full paths in includes and requires, less time spent on resolving the OS paths.

9. If you need to find out the time when the script started executing, $_SERVER[’REQUEST_TIME’] is preferred to time()

10. See if you can use strncasecmp, strpbrk and stripos instead of regex

11. str_replace is faster than preg_replace, but strtr is faster than str_replace by a factor of 4

12. If the function, such as string replacement function, accepts both arrays and single characters as arguments, and if your argument list is not too long, consider writing a few redundant replacement statements, passing one character at a time, instead of one line of code that accepts arrays as search and replace arguments.

13. It’s better to use switch statements than multi if, else if, statements.

14. Error suppression with @ is very slow.

15. Turn on apache’s mod_deflate

16. Close your database connections when you’re done with them

17. $row[’id’] is 7 times faster than $row[id]

18. Error messages are expensive

19. Do not use functions inside of for loop, such as for ($x=0; $x < count($array); $x) The count() function gets called each time.

20. Incrementing a local variable in a method is the fastest. Nearly the same as calling a local variable in a function.

21. Incrementing a global variable is 2 times slow than a local var.

22. Incrementing an object property (eg. $this->prop++) is 3 times slower than a local variable.

23. Incrementing an undefined local variable is 9-10 times slower than a pre-initialized one.

24. Just declaring a global variable without using it in a function also slows things down (by about the same amount as incrementing a local var). PHP probably does a check to see if the global exists.

25. Method invocation appears to be independent of the number of methods defined in the class because I added 10 more methods to the test class (before and after the test method) with no change in performance.

26. Methods in derived classes run faster than ones defined in the base class.

27. A function call with one parameter and an empty function body takes about the same time as doing 7-8 $localvar++ operations. A similar method call is of course about 15 $localvar++ operations.

28. Surrounding your string by ‘ instead of ” will make things interpret a little faster since php looks for variables inside “…” but not inside ‘…’. Of course you can only do this when you don’t need to have variables in the string.

29. When echoing strings it’s faster to separate them by comma instead of dot. Note: This only works with echo, which is a function that can take several strings as arguments.

30. A PHP script will be served at least 2-10 times slower than a static HTML page by Apache. Try to use more static HTML pages and fewer scripts.

31. Your PHP scripts are recompiled every time unless the scripts are cached. Install a PHP caching product to typically increase performance by 25-100% by removing compile times.

32. Cache as much as possible. Use memcached - memcached is a high-performance memory object caching system intended to speed up dynamic web applications by alleviating database load. OP code caches are useful so that your script does not have to be compiled on every request

33. When working with strings and you need to check that the string is either of a certain length you’d understandably would want to use the strlen() function. This function is pretty quick since it’s operation does not perform any calculation but merely return the already known length of a string available in the zval structure (internal C struct used to store variables in PHP). However because strlen() is a function it is still somewhat slow because the function call requires several operations such as lowercase & hashtable lookup followed by the execution of said function. In some instance you can improve the speed of your code by using an isset() trick.

Ex.
if (strlen($foo) < 5) { echo “Foo is too short”; }
vs.
if (!isset($foo{5})) { echo “Foo is too short”; }

Calling isset() happens to be faster then strlen() because unlike strlen(), isset() is a language construct and not a function meaning that it’s execution does not require function lookups and lowercase. This means you have virtually no overhead on top of the actual code that determines the string’s length.

34. When incrementing or decrementing the value of the variable $i++ happens to be a tad slower then ++$i. This is something PHP specific and does not apply to other languages, so don’t go modifying your C or Java code thinking it’ll suddenly become faster, it won’t. ++$i happens to be faster in PHP because instead of 4 opcodes used for $i++ you only need 3. Post incrementation actually causes in the creation of a temporary var that is then incremented. While pre-incrementation increases the original value directly. This is one of the optimization that opcode optimized like Zend’s PHP optimizer. It is a still a good idea to keep in mind since not all opcode optimizers perform this optimization and there are plenty of ISPs and servers running without an opcode optimizer.

35. Not everything has to be OOP, often it is too much overhead, each method and object call consumes a lot of memory.

36. Do not implement every data structure as a class, arrays are useful, too

37. Don’t split methods too much, think, which code you will really re-use

38. You can always split the code of a method later, when needed

39. Make use of the countless predefined functions

40. If you have very time consuming functions in your code, consider writing them as C extensions

41. Profile your code. A profiler shows you, which parts of your code consumes how many time. The Xdebug debugger already contains a profiler. Profiling shows you the bottlenecks in overview

Prabhas Gupte is freelance software developer and consultant.

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Random image example

Thursday, February 12th, 2009

This is a simple random image script which is ideal for displaying basic images from a text file . In future examples we will expand on this and build some simple banner rotation systems.

The first step that you need to do is to create your file for storing your images and then insert the names of the images.

In the example here I called the file images1.txt .

Each one of the entries is on a seperate line and in this case because I stored the files in a sub-directory I inserted that also . the structure of the file was like this

image/banner1.gif
image/banner2.gif
image/banner3.gif

and so on. Now we get to the script that will display a random image and again this is straight forward enough.

<?php
#random images example
#this is your file
$file = “images1.txt”;
#open the file
$fp = file($file);
#generate a random number
srand((double)microtime()*1000000);
#get one of the entries in the file
$random_image = $fp[array_rand($fp)];
#display the entry
echo “<img src=’$random_image’></img>”;
?>

Nothing ground breaking here , we open a file , we then generate a random number, we then get a random entry from the file and store this in the variable $random_image and then we output this as some HTML.

Note that in this example we have saved this as a seperate file and included it on the page . If the file was called random.php then we put the following code where we want the image to appear

<?php include(”random.php”); ?>

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