Die Rolling

We are going to modify the previous die rolling application so that it rolls the die a chosen number of times and keeps a tally of how many of each number has been rolled. The user will click on the die image to start rolling.

Design the interface

Draw your interface like this:

Name the text box txtTotalRolls, set its text to be 0 (Make sure it is big enough for 6 digits)

Name the pink coloured labels lblOnes, lblTwos, lblThrees etc These will show the total of each number rolled. Set their captions to be 0. (Make sure that they are wide enough to take 6 digits.

Name the picture imgDie. We will click it to start.

Name the exit button cmdExit.

Write the Code

We will set up nine variables called totalRolls, counter, dieRoll, totalOnes, totalTwos, totalThrees, totalFours, totalFives, and totalSixes to store the totals.
At the start of the program, we will set the value of most of the variables to 0 (this is called initialising them) totalOnes=0: totalTwos=0 etc (The colon : can be used to put more than one line of code on the same line)
To get the total number of rolls that the user enters, we will use the line:

totalRolls = txtTotalRolls.text

This takes the value the user puts in the text box and stores it in the variable totalRolls

We will use a For...Next loop to repeat the die rolling the required number of times.

A For Next loop looks a bit like this:

For Counter = 1 to 5

Eat lolly

Next Counter

The Counter is a variable that counts up from 1 to 5. The first time through the loop, counter has the value 1, the second time through counter has the value 2, etc. After the fifth time through, counter has the value 5, so a total of 5 lollies will be eaten.

So our code for the loop will be:

For counter = 1 to totalRolls

Roll Die and add to total

Next counter

To keep count of how many of each number there have been, we will use this code:

totalOnes = totalOnes + 1

(totalOnes is assigned the value totalOnes plus 1)

This means take whatever value is stored in the variable totalOnes, add 1 to it, then store the value back in the variable totalOnes.
Because our code is getting complicated, so we will use comments explaining it as we go.

Comment lines make it easier for ourselves and other programmers to understand the code. They make finding errors easier.

Comment lines start with an apostrophe ' and are ignored by the computer. You can also add comments to the end of another line. Everything after the apostrophe will be ignored.

' this is a comment

So our code for when the die picture is clicked will be as follows:

Private Sub imgDie_Click()

Dim totalRolls, counter, dieRoll, totalOnes, totalTwos, totalThrees, totalFours, totalFives, totalSixes as Long

Randomize

totalOnes=0: totalTwos=0: totalThrees=0: totalFours=0:totalFives=0: totalSixes=0 'initialise total counters

totalRolls = txtTotalRolls.text 'get the total number of rolls

For counter = 1 to totalRolls

DieRoll = Int (Rnd*6)+1    'roll die

Select Case DieRoll

Case 1
      totalOnes=totalOnes+1

Case 2
      totalTwos=totalTwos +1

Case 3
      totalThrees=totalThrees +1

Case 4
      totalFours=totalFours +1

Case 5
      totalFives=totalFives+1

Case 6
      totalSixes=totalSixes+1

End Select

Next counter

'output the totals for each number

lblOnes.caption=totalOnes
lblTwos.caption=totalTwos
lblThrees.caption=totalThrees
lblFours.caption=totalFours
lblFives.caption=totalFives
lblSixes.caption=totalSixes

End Sub

Attach code for when the exit button is clicked

Test your Application

Test your application, taking careful note of any problems, especially with regard to label sizes. You may need to adjust font sizes or make labels autosize (watch out they don't autosize over top of each other!)

You may notice that the program can crash if the user puts in something other than a number into the text box. Can you work out a way to solve this problem?