VB CONSOLE SUMMER WORK. Introduction into A Level Programming

Transcription

1 VB CONSOLE SUMMER WORK Introduction into A Level Programming

2 DOWNLOAD VISUAL STUDIO You will need to Download Visual Studio Community 2013 to create these programs en-us/products/visual-studiocommunity-vs.aspx

3 INSTRUCTIONS For each of the tasks, paste screenshots of completed code into the Answer Document. Where questions are asked, write the answers in the spaces provided on the document

4 1. PLAYING WITH VARIABLES COPY and Paste this code in VB declare variables Dim name As String = "Homer Simpson " Dim weight As Integer = 239 Dim height As Decimal = 5.9 Dim PossibleBrainDamage = True Dim stagename As String = "Wide Load QUESTION 1: Why when you run this script, does nothing happen? QUESTION 2 What is the difference between an INTEGER and DECIMAL?

5 2. PLAYING WITH VARIABLES declare variables Dim name As String = "Homer Simpson " Dim weight As Integer = 239 Dim height As Decimal = 5.9 Dim PossibleBrainDamage As Boolean = True Dim stagename As String = "Wide Load use variables in a sentence Console.WriteLine("Weighing an incredible " & weight & " pounds and a staggering " & height & " feet high ") QUESTION 1: What is the difference between a String and an Integer? TAKE NOTE: Using the & symbol like this is called concatenation! TASK:: Try to finish the introduction above by concatenating (joining) all the other variables onto the sentence.

6 3. PLAYING WITH VARIABLES declare variables Dim percentage As Decimal = "92.4" Dim correct As Boolean = "True" Console.WriteLine("Doesn t expecting the unexpected make the unexpected become the expected?? ") Console.WriteLine("This fact is absolutely " & correct ") Console.WriteLine("percentage " & " % of students agree!") BOOLEAN is used when we want to store True or False values QUESTION 1: What does do? RUN the code without it to find out!

7 4. PLAYING WITH VARIABLES COPY and Paste this code in VB declare variables Dim name, scent As String name= "Stewie" scent = "methane gas expulsion" Console.WriteLine("My bestest friend " & name & " smells of " & scent & "!") TASK: play around with the variables seen here to create your own sentence about your best mate!

8 PLAYING WITH VARIABLES COPY and Paste this code in VB declare variables Dim name, scent As String name= "Stewie" scent = "methane gas expulsion" Console.WriteLine("My bestest friend " & name & " smells of " & scent & "!") QUESTION 1: the variables here are declared in a different way from slide 2, 3 and 4. WHAT is different? WHICH method do you prefer?

9 DATA TYPES WHY DOES IT MATTER? When you create a VARIABLE, you are asking the computer to STORE something in its MEMORY Some DATA TYPES can take more memory than others. For example, a STRING - which can store lots of characters - can use a lot more memory then CHAR which stores a single character. Again, storing a DECIMAL takes more memory then storing an INTEGER. A bad program will choose poor data types to store information. This slows the program down because it uses more memory than necessary. EVEN WORSE, a program can crash when it expects to see one data type but gets another!! This is often called a RUN TIME ERROR

10 6. PROBLEMS WITH YOUR VARIABLES.? Dim x, y, total As Integer Console.WriteLine("Enter the value of x ") x = Console.ReadLine() Console.WriteLine("Enter the value of y ") y = Console.ReadLine() total = x + y Console.WriteLine("The total is " & total) TASK: Copy and paste this code into VB. Enter TWO numbers when prompted. THEN Run the program again but this time SPELL the number e.g. eight not 8. Question 1: Explain WHAT happens.

11 8. DATA TYPES Data Type Storage (bits, bytes etc) Value range Boolean Byte Integer Double Decimal Char String Boolean Date RESEARCH ACTIVITY: You will need to investigate the difference between signed and unsigned

12 MY BEST FRIEND THE COMPUTER Dim name, colour As String Console.WriteLine("S up dude. What s your name?") name = Console.ReadLine() Console.WriteLine("Whatever, " & name & ". Your mum s got gold teeth!") Console.WriteLine("Roses are red, violets are...") colour = Console.ReadLine() Console.WriteLine("Yes, yes. Roses are red, violets are " & colour & ". God made me pretty, but what happened to you??") NOTICE: that Console.ReadLine() lets us store information in a variable?? TASK: Write your own conversation with the computer. You must use at least 2 variables

13 9.PLAYING WITH FORMATTING TRY THIS ROBOT HUMOUR Console.ForegroundColor = ConsoleColor.Red Console.WriteLine("What s red and bad for your teeth?") Console.WriteLine("A brick") Console.ForegroundColor = ConsoleColor.Yellow Console.WriteLine("What's yellow and doesn't float?") Console.WriteLine("A bulldozer") TASK: Show the words red, amber and green on screen. Colour the words suitably.

14 10. MATHEMATICAL OPERATORS Dim x, y, total As Integer Console.WriteLine("Enter the value of x ") x = Console.ReadLine() Console.WriteLine("Enter the value of y ") y = Console.ReadLine() total = x + y Console.WriteLine("The total is " & total) Symbols Used: + Add - Minus * Multiply / Divide Mod Finds the remainder WRITE a program that divides a number entered by a user WRITE a program that displays any times table the user requests

15 11. MATHEMATICAL OPERATORS & FORMATTING NUMBERS Dim z As Double Z = 23 ^ 3 this sets Z to (the cube of 23) Dim K As Integer K = 23/5 this sets K to 4. Int will strip out any decimal places! Dim X As Integer = 100 Dim Y As Integer = 6 Dim Z As Integer Z = X Mod Y this sets Z to 4 Dim A As Double = Dim b As Double = 4.13 Dim C As Double C = A Mod B this sets C t Modulus finds the remainder Console.ForegroundColor = ConsoleColor.White Console.WriteLine("Enter a number") num = Console.ReadLine() Console.WriteLine("The number is " & num) Console.ForegroundColor = ConsoleColor.Green Console.WriteLine("To 2d.p it is " & Format(num, "###.00")) Console.WriteLine("As a percentage " & Format(num, "###.00%")) Console.WriteLine("As currency " & Format(num, " ###.00")) WRITE: a program that will read 3 integers and display the sum ENTER: the length, width and depth of a swimming pool. Calculate the volume of water and display it. WRITE: a program that will display six random numbers between 5 and 10 EXTENSION: WRITE: a program to enter an amount of money as a whole number e.g. 78. Now display the minimum number of 20s, 10s, 5s, 2s and 1s that make up this amount. For example, the value 78 would give 3 twenty pound notes, 1 ten pound note, 1 five pound note, 1 two pound coin and 1 pound coin.

16 SELECTION: IF STATEMENTS IF statements allow the COMPUTER to choose which code to run. They do this by working out if a condition is TRUE or FALSE: IF [this condition is true] Then Do this code End If HERE IS AN EXAMPLE: Dim name As String = "Pete" declare variable Console.WriteLine("Enter your name") name = Console.ReadLine() If name = "Pete" Then If this is true then Console.WriteLine("Hi " & name) End If

17 LET S SUP IT UP If, ElseIf and Else can be used to make the bog standard if statement more SOPHISTICATED: IF [this condition is true] THEN Do this code ElseIf [this condition is true] THEN Do this code Else [If all conditions are false] Do this code End If The ELSE keyword catches any other possibility if all the other conditions return FALSE.

18 12. SELECTION (USING IF STATEMENTS) Dim choice As Char declare variables Console.WriteLine("Choose a one liner") Console.WriteLine("A: My Bestest one liner") Console.WriteLine("B: My Second bestest") Console.WriteLine("C: The crap one I use at parties to break the ice") choice = Console.ReadLine() COPY AND PASTE THIS INTO VB If choice = "A" Then Console.WriteLine("I want to die peacefully in my sleep, like my grandfather.. Not screaming and yelling like the passengers in his car") ElseIf choice = "B" Then Console.WriteLine("Just read that 4,153,237 people got married last year, not to cause any trouble but shouldn't that be an even number?") Else Console.WriteLine("I hate it when I am about to hug someone really sexy and my face hits the mirror..") End If TASK: We can use as many ELSEIFs statements as we want to increase the sophistication of a program!! Add your own ElseIf to the program above!

19 13. YOUR TURN IF STATEMENTS WRITE a program that asks the user to enter your name and a password. IF the password = Teapot, THEN say "Welcome " & then your name. OTHERWISE show the message "Who the hell are you??" WRITE a program to ask the user what 2*2 is. Say "Well done, you have an IQ of a chimp" if they get it right and "What are u, like 2?" if they get it wrong.