Learning Objectives:
You will be able to create an array
You will be able to create a switch
You will be able to identify the use of conditional statements.
Homework:
Read: Chapter 3
Create: Flow Chart for buying a comptuer or a car and Link to Homework page!
Watch: How to do a Flow Chart
Watch: Big Bang Theory Friendship Algorith shows why you do a flow chart.
Topics Covered:
Flow Charts help you define your logic!
Watch a flow chart in action
Array is a variable on steroids. (Array's have several values under the same variable name.) You have to declare an array!
var mynewarray= new Array()
mynewarray[0], mynewarray[1],mynewarray[2] Notice the array number starts with 0.
Conditional Statements (Java script's method of testing the environment)
if statement - use this statement if you want to execute some code only if a specified condition is true
if (condition)
{ code to be executed if condition is true }
if...else statement - use this statement if you want to execute some code if the condition is true and another code if the condition is false
if (condition)
{ code to be executed if condition is true }
else
{ code to be executed if first condition is not true }
if...else if....else statement - use this statement if you want to select one of many blocks of code to be executed - >Note: You may want to use Switch if you have more than 3 conditions
Syntax
if (first_condition)
{ code to be executed if condition is true }
else if (second_condition)
{ code to be executed if first condition is not true and this condition is true}else
{ code to be executed if 1st & 2nd condition is not true }
switch statement - use this statement if you want to select one of many blocks of code to be executed
switch(n) {
case 1:
execute code block 1
break
case 2:
execute code block 2
break
default:
code to be executed if n is different from case 1 and 2
}
Two different kind of loops In JavaScript, there are:
1. for - loops through a block of code a specified number of times
for (variable=startvalue;variable<endvalue;variable=variable+increment)
{
code block
}2. while - loops through a block of code while a specified condition is true
while (variable<endvalue)
:
{
code block
}Logical Operators
Operator Description Example && and x=9
y=4(x < 10 && y > 1) returns true
|| or x=6
y=3(x==5 || y==5) returns false
! not x=10
y=5!(x==y) returns true
Terms:
Flow Charts, Conditional Statements, if else, switch, Function, Operators and Argument
