Business VPN? Assignment grades will be posted in Collab
jQuery Libraries jQuery Core library, provides selectors and basic effects http://jquery.com/ jQuery UI Provides user Interface functions, e.g. Tabs http://jqueryui.com/ (See Demos) jQueryplugins Hundreds of functions and effects http://plugins.jquery.com/
Another jQuery Example Create a class for notes that can be turned on an off Show jQuery features: Manipulation: new text added Traversing: moving between elements Dynamic CSS: add styles dynamically to elements
Overview Today we shift to PHP – a server-side programming language
Client vs. Server Side All programs are human written sequences of commands that control the computer Programs are first “compiled” into a machine language When a program is “executed,” it produces an effect
Client vs. Server Side In web programming, web pages can have either server-side or client-side programs embedded in them Server-side code gets executed before the page is delivered to the browser Client-side code gets executed after the page is delivered to the browser
PHP PHP is a simple server-side programming language It was invented in 1994 by RasmusLerdorf, a Danish Canadian, as a way to simplify the process of writing server-side programs These older programs were called “CGI scripts” Originally PHP stood for “Personal Home Page,” now it just means PHP ...
Exercise 1: Hello, World! Create a new file, hello.php Create an H1 Element called “Introduction to PHP” Create an H2 Element called “Exercise 1” Enter the following code: <p> <?php echo “Hello, World!”; ?> </p>
Observations PHP files must end in .php Otherwise, not executed, treated as text PHP code must live inside of the opening and closing “tags” <?php and ?> This looks like XML but it is not Anything outside of these tags is regular content, e.g. plain text, HTML, or XML echo is just a function that prints its argument to the screen echo does note require parantheses Your browser knows nothing about the PHP
Exercise 2: Variables Comment out your first echo statement Define a variable to hold the string “Hello, World!” Use echo to print the variable to the screen
Variables Always prefixed by $ Variables hold values VariableS are assigned values with the = sign Variables are always on the left
Exercise 3: Variable Types Comment out your last echo statement Create a new variable called $notd (for “number of the day”) and give it a numeric value, e.g. $notd = (42 * 5) + 29; Do not use quotes Append text to your message variable $message .= “The message of the day is: ”; Then echo the message and the notd together echo “$message $notd”;
Observations Values can be strings, numbers, or other things Strings are always quoted (in single or double quotes) Numbers are never quoted Number can be the result of an equations Operators: + - * / (also: ^ and %)
Exercise 4: Arrays Create a new file rex.php Invoke the file() function to grab a file from the web and assign the return value to the variable $contents Use the URL from post [8.1] on the blog $url = '.http://classics.mit.edu/Sophocles/oedipus.pl.txt’; $contents = get($url); Invoke echo to print out $contents to screen
Observation What do we see? PHP is telling us that $contents is an array, not a string What is an array?
Arrays Arrays are built-in data structures in the PHP language A data type that holds other data types (strings, numbers, other arrays) Each stores a list of values The items in the list are indexed a number starting with 0 Let’s look back at our example ...
Exercise 5 Iterate through the $contents array using the foreach() function Then iterate through the $contents array using the for() function
Observations Arrays have a length, or size The size is always 1 greater than the last index value Since the index begins with “0” Iterating through arrays allows you to modify each item in the array Text files are often represented as arrays
Exercise 6 Using the foreach() function, format each line Skip the first 5 lines Remove the trailing new line wrap each $line in paragraph tags