1. ICS 3U
Tuesday, September 21st

2. Conditional Statements If Statements
If statements are used in code to make decisions ...
If a condition is true, then something is done
If the condition is false, something else may happen
An example would be doing one thing if the user enters an even number, and something else if an odd number is entered

3. Basic Structures Three types of if statements: Simple If
If / Else
If / Else If / Else
Simple If
Something is done if the boolean expression is true
If (boolean expression) then
Statements that are executed for true

4. Basic Structures (con’t)
If / Else
Something is done when true, and something else is done when false
If (boolean expression) then
- statements evaluated if true
Else
- statements evaluated if false

5. Basic Structures (con’t)
If / Else If / Else
Multiple boolean expressions are included
If (boolean expression) then
- statements if this boolean expression is true
Else If (boolean expression) then
- statements if first expression is false, but this one is true
Else
- statements if all boolean expressions are false

6. Boolean Expressions / Variables
A boolean expression is an expression that evaluates to true or false (a boolean result)
They involve relational operators
(<, >, !=, ==, <=, >=)
The result of a boolean expression can be assigned to a boolean variable.
Boolean variables are used to enhance the readability of programs, and to help with debugging
When boolean variables are converted to integers, they have a value of 0 or 1 (0 = false, 1 = true)

7. Boolean Expressions / Variables Example
Example: if age > 18 price = Better example (use of boolean variable): adult = age > 18 if adult

8. Logical Operators
In addition to the relational operators, we can use logical operators:
AND &&
OR ||
NOT !
These are used to combine boolean expressions to create new and more complext boolean expressions
Remember they have an order of operations:
NOT, AND, OR  NAO

9. Logical Operator Examples
Example: if adult && passholder then price = if tired || hungry then go home if ! happy then tell a joke

10. Logical Operator Rules
AND && - both expressions have to be true
This course is ICS3U and all students are 15 yrs old
This course is ISC 3U and the teacher is Miss Nieuwenhuis
OR || - only one of the expressions needs to be true
It is a day 1 or it is a day 2
This course is ICS 3U or all students are 15 yrs old
NOT ! – the opposite
! (age < 15)
! (weather is sunny)

11. ActionScript Syntax

12. Work Time!  Programming Exercises – see wiki
NEW Programmers – Stay UP HERE with me for some additional examples

13. Examples Write if statements for the following:
User has entered in a number, output if the number is greater than 100
User has entered in their mark, output if the grade is a pass or a fail
User has entered in their age, compare their age to yours output younger, same age or older.