1. Tutorial 4 Decision Making with Control Structures and Statements Section A - Decision Making
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

2. Tutorial 4A Topics Section A - Decision Making if statements
if…else statements
Nested if statements
switch statements
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

3. Decision Making Decision Making
Process of determining the order in which statements execute in a program
AKA – flow control
Decision-Making Structures
Special type of JavaScript statements used for making decisions
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

4. Decision Making if Statements
Used to execute specific programming code if the evaluation of a conditional expression returns a value of true
“Do this or don’t do this”
Syntax (3 primary parts)
if (conditional_expression) {
statement(s); }
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

5. Decision Making if Statements Operation Command block
If the conditional expression is true, the statement(s) is/are executed
Control then continues to subsequent code
Command block
Multiple statements contained within a set of braces (require curly braces)
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

6. JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

7. JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

8. JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

9. Decision Making if Statements Conditional Expression Can consist of:
Comparison operators
Logical operators
Combination of the two
Must resolve to Boolean value
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

10. Decision Making if…else Statements
Used to execute one set of code if the evaluation of a conditional expression returns a value of true, otherwise executes another set of code
“Do this or do something else”
Syntax
if (conditional_expression) {
statement(s);
} else { }
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

11. JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

12. Decision Making Nested if and if…else Statements Nested statements
Statements contained within other statements
Syntax (variable)
if (conditional_expression) {
statement(s); }
} else {
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

13. JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

14. JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

15. Decision Making switch Statements
Controls program flow by executing a specific set of statements, depending on the value of an expression
Syntax switch (expression) {
case label1:
statement(s);
break;
case label2:
default: }
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

16. Decision Making switch Statements Case labels Break statement
Identify specific code segments
Can use a variety of data types as case labels
Break statement
Used to exit switch statements
Default label
Contains statements that execute when the condition expression doesn’t match any of the case labels
JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

17. JavaScript Tutorial 4 -Decision Making with Control Structures and Statements

18. JavaScript Tutorial 4 -Decision Making with Control Structures and Statements