Web Systems Development (CSC-215) Lecture 3: Introducing PHP Wednesday 7th February 2018

Functions User defined Inbuilt PHP function An integer representation of time using Unix timestamp convention.

PHP Manual Reference

Using the function

Get date from 17 days ago

Variable Scope Local variables, e.g., arguments to a function

Out of scope

Re-arranged

Or passed as argument Longdate modified

Global Variables Avoid unless absolutely necessary because its bad programming practice.

Static Variables

Static Variables Only predetermined values allowed

Expressions

Booleans TRUE & FALSE

Literals and Variables

Expressions and Statements

Operators

Precedence

Relational Operators

Identity Operator Only 1 is printed

Not identical Only 2 is printed

Conditionals

Conditionals

Conditionals

Switch Default and break, as in C++

Loops

Loops

Loops

Class Activity Print the current date and time as per the given formatting, and then print 9 future date and time values in 12 hour increments. Maintain HTML formatting as well (h1 and p tags used). Set the correct time zone for WampServer if needed.

Lecture content adapted from chapters 2 & 3 of Learning PHP, MySQL, JavaScript, CSS & HTML5, 3rd Edition, by Robin Nixon.