4. PHP functions
Documented PHP functions
http://us2.php.net/quickref.php
You can create your own functions too
9/4/2017 CS346 PHP 4
5. 9/4/2017 CS346 PHP 5
Objectives
What is PHP?
How does a PHP script work with a
Web Browser and a Web Server?
What software and components you
need to get started with PHP?
To create and run a simple PHP script
6. 9/4/2017 CS346 PHP 6
What Is PHP?
PHP, PHP Hypertext Preprocessor
Server-side scripting languages for creating
dynamic web pages
7. 9/4/2017 CS346 PHP 7
PHP advantages
Advantages of Using PHP to enhance Web
pages:
Easy to use
Simpler than Perl
Open source
Multiple platform.
8. 9/4/2017 CS346 PHP 8
How PHP Pages are Accessed
and Interpreted
Client: Web browser Web server
1.Form submitted with a submit button
2.----- Action sends a request to the php file in server
3. Receive the request, find the file,
and read it
4. Execute the PHP commands
5. Send the results back
6. ---- results returned as HTML file
7. Web browser renders the HTML file, displaying the results
9. 9/4/2017 CS346 PHP 9
Getting Started with PHP
To develop and publish PHP scripts you need:
A client machine with a basic text editor and
Internet connection
• Prepare a text file with .php extension
FTP or Telnet software
• Upload the file.php to the server
A Web server with PHP built into it
• Process the file.php
10. 9/4/2017 CS346 PHP 10
WHH Note
This means that a browser e.g. IE or
Firefox on the client computer will not
recognize or render a file with extension
.php
How do you check your PHP script before
submission to server?
11. 9/4/2017 CS346 PHP 11
Getting Started with PHP
Set up development computer as a server
Laptop contains a server and a browser environment
Laptop is also set up as a Web server - WAMPserver
• Windows Apache, MySQL, PHP
Client machine: PC, XP, editors, browsers
Internet connection not needed
Use copy and paste to transfer the scripts
For class demos:
localhost or 127.0.0.1 or cs346 server
12. 9/4/2017 CS346 PHP 12
Exploring the Basic PHP
Development Process
The basic steps you can use to develop and
publish PHP pages are:
1. Create a PHP script file and save it to a local disk
• Test on localhost until satisfied
2. Use FTP to copy the file to the server
3. Access your file via URL on server using a
browser
• IE, Netscape, Opera, etc.
13. 9/4/2017 CS346 PHP 13
Check PHP installation
Create a simple PHP script, called
phpinfo.php
The PHP script starts with a <?php tag and
ends with ?>
Between these tags is a single PHP
statement: phpinfo();
Copy the file to a directory of local server
For WAMP: wamp/www
Access the file with a browser
http://localhost/checkphp.php
15. Checking the server set up
Upload the phpinfo.php to cs346 server
E.g. to huen/m00
Click on the link
http://cs346.cs.uwosh.edu/huen/m00/phpinfo.php
Check the various environments:
Apache
MySQL
PHP functions
variables
9/4/2017 CS346 PHP 15
17. 9/4/2017 CS346 PHP 17
Creating a PHP Script File
Create PHP script welcome.php
Starts with a <?php tag and ends with ?>
Between these tags is a single PHP print
statement
Copy the file to C:wampwww
Access the file with
http://127.0.0.1/welcome.php
Demo on localhost
Demo on cs346 server
18. Similarly for other PHP scripts
Upload welcome.php to huen/m00
Click on
http://cs346.cs.uwosh.edu/huen/m00/welcome.php
9/4/2017 CS346 PHP 18
<?PHP
/* welcome.php */
print ("<h1 style="color: blue;">Welcome to PHP, CS346 class!</h1>");
/* Note the combination of html tags and css */
?>
20. 9/4/2017 CS346 PHP 20
Alternative PHP Delimiters
You can alternatively start your PHP scripts
with the <script> tag as follows:
<script language="PHP">
print ("A simple initial script");
</script>
If short_open_tag enabled in its configuration
file (php.ini), you can use <? and ?>.
If asp_tags is enabled in the PHP
configuration file, you can use <% and %>
as delimiters.
21. 9/4/2017 CS346 PHP 21
Proper Syntax
If you have a syntax error then you have
written one or more PHP statements that are
grammatically incorrect in the PHP language.
The print statement syntax:
print ( "Your message to print" );
Enclose message
in quotation
marks
Message to Output
End in a
semi-colon
Parenthesis are
optional
22. 9/4/2017 CS346 PHP 22
If syntax is wrong
<?php
print ( "Welcome to PHP, CS346 class!);
?>
23. 9/4/2017 CS346 PHP 23
A Little About PHP's Syntax
Some PHP Syntax Issues:
Be careful to use quotation marks, parentheses, and
brackets in pairs.
Most PHP commands end with a semicolon (;).
Be careful of case.
PHP ignores blank spaces.
24. 9/4/2017 CS346 PHP 24
Embedding PHP Statements Within
HTML Documents
One way to use PHP is to embed PHP scripts
within HTML tags in an HTML document.
Save the file first with extension html
Validate the html file
Change the extension to php
Access the script by URL on server
25. 9/4/2017 CS346 PHP 25
<html xmlns = "http://www.w3.org/1999/xhtml">
<head>
<title>HTML With PHP Embedded </title>
</head>
<body>
<p style = "font-family:sans-serif; font-size:36;
color:yellow; background-color:green">
Welcome To My Page!
<?PHP
print ("<br /> Using PHP is not hard!");
?>
<br /> and you can learn it quickly!</p>
</body>
</html>
27. 9/4/2017 CS346 PHP 27
Using Backslash () to Generate
HTML Tags with print()
Sometimes you want to output an HTML tag
that also requires double quotation marks.
Use the backslash (“”) character to signal that the
double quotation marks themselves should be
output:
print ("<font color="blue">");
The above statement would output:
<font color="blue">
28. 9/4/2017 CS346 PHP 28
Using Comments with
PHP Scripts
Comments enable you to include
descriptive text along with the PHP
script.
Comment lines are ignored when the script
runs; they do not slow down the run-time.
Comments have two common uses.
• Describe the overall script purpose.
• Describe particularly tricky script lines.
29. 9/4/2017 CS346 PHP 29
Using Comments with PHP Scripts
Comment Syntax - Use //
standalone
<?php
// This is a comment
?>
Can be placed on Same line as a
statement:
<?php
print ("A simple initial script");
//Output a line
?>
30. 9/4/2017 CS346 PHP 30
Example Script with Comments
1. <html> <head>
2. <title> Generating HTML From PHP</title> </head>
3. <body> <h1> Generating HTML From PHP</h1>
4. <?php
5. //
6. // Example script to output HTML tags
7. //
8. print ("Using PHP has <i>some advantages:</i>");
9. print ("<ul><li>Speed</li><li>Ease of use</li>
<li>Functionality</li></ul>"); //Output bullet list
10. print ("</body></html>");
11. ?>
31. 9/4/2017 CS346 PHP 31
Alternative Comment Syntax
PHP allows a couple of additional ways to
create comments.
<?php
phpinfo(); # This is a built-in function
?>
Multiple line comments.
<?php
/*
A script that gets information about the
PHP version being used.
*/
<? phpinfo(); ?>
32. 9/4/2017 CS346 PHP 32
Summary
HTML pages are static and cannot interact with
users
PHP is a free, open source technology that
enables documents to generate dynamic content
PHP script has the extension of .php
PHP script may be standalone or
Can be embedded in an HTML document
33. 9/4/2017 CS346 PHP 33
Summary
Resources needed for development:
Web server with built-in PHP
a client machine with a basic text editor,
browser, and internet connections
FTP or Telnet software to send the script to
the server
34. 9/4/2017 CS346 PHP 34
Summary
PHP script process:
write the PHP script file
copy the script file to the Web server
access the file with a Web browser
Comments can be proceeded with
two forward slashes (//)
or #
or enclosed in /* and */