COMP6015

1

• COMP6015
• An
• Introduction
• to
• Computer Programming
• Lecture 04

2
Introduction to PHP

• Arrays
• The built-in function count() tells you how many
  elements are in an array
• fruit array('banana','papaya')
• print count(fruit)
• Prints 2

3
Introduction to PHP

• Control Structures
• You can use looping structures such as for and
  while
• for (i 4 i lt 8 i)
• print "I have eaten i bagels today.\n"
• prints
• I have eaten 4 bagels today.
• I have eaten 5 bagels today.
• I have eaten 6 bagels today.
• I have eaten 7 bagels today.

4
Introduction to PHP

• Control Structures
• So does
• i 4
• while (i lt 8)
• print "I have eaten i bagels today.\n"
• i

5
Introduction to PHP

• Control Structures - if and elseif
• if (user_count gt 200)
• print "The site is busy right
  now!"
• elseif (user_count gt 100)
• print "The site is sort of active right
  now!"
• else
• print Only user_count user logged on."

6
Introduction to PHP

• Control Structures - if and elseif
• (Code is also written this way)
• if (user_count gt 200)
• print "The site is busy right
  now!"
• elseif (user_count gt 100)
• print "The site is sort of active right
  now!"
• else
• print Only user_count user
  logged on."

7
Introduction to PHP

• Control Structures
• The rule of thumb about operators also applies to
  control structures.
• You can use
• switch
• do...while
• even the ?
• construct.

8
Introduction to PHP

• Control Structures
• Switch
• switch(var1)
• case 1 print(We found one\n)
• case 2 print(We found two\n)
• case 3 print(We found three\n)
• default print(We did not find any!\n)

9
Introduction to PHP

• Control Structures
• dowhile
• do
• print(var times\n)
• var
• while (var lt var2)

10
Introduction to PHP

• Control Structures
• Ternary operator (? )
• print ( (var gt var2) ? var var2)
• OR
• var (test_var "December") ?
• "Merry Christmas" "It is not Christmas
  yet"

11
Introduction to PHP

• One of PHP's most handy features is its ability
  to automatically load the values of variables
  from forms into variables in PHP. This makes form
  processing fairly easy.
• So, a submitted form with input field such as
  this
• ltINPUT TYPETEXT NAME"name" VALUE"Glen
  Morris"gt
• when processing the page with PHP, the variable
  name has a value of Glen Morris.
• So, we can do things such as
• echo "Hi name!"
• or test its value
• if (name "Glen Morris")
• echo "Please check your email."

12
Introduction to PHP

• NOTE
• Forms manipulation
• will be covered in
• much more detail in
• a subsequent course.

13
Introduction to PHP

• EXERCISE
• Develop PHP code to address the following
• Insert the numbers 1 20 into an array
• Print out the even numbers from the array - 5
  values to a line
• Print out the odd numbers from the array 4 to a
  row, starting with the largest.
• Output the numbers from the array 1 to a row,
  but if the value is a multiple of 4, output the
  word BINGO instead.