Learn to Program with Small Basic

Figure 6-2: The text window waiting for input from
your user
When Small Basic runs the statement radius = TextWindow.ReadNumber(),
it waits for the user to enter a number and press enter. The program won’t
read what the user types until they press enter. When the user presses
enter, the program grabs the user input and assigns it to the radius variable.
The program then continues with the statement after the ReadNumber()
method.
Now that you’ve accepted the radius from your user, all that’s left is to
compute the area and display the result. Listing 6-2 shows the complete
program.
1 ' CircleArea3.sb
2 TextWindow.Write("Please enter a radius; then press : ")
3 radius = TextWindow.ReadNumber()
4
5 area = 3.1416 * radius * radius
6 TextWindow.WriteLine("Area = " + area)
Listing 6-2: Letting the user enter the radius
Let’s see what the output looks like if you enter a radius of 8:
Please enter a radius; then press : 8
Area = 201.0624
Try it out for yourself!
A Moment of Silence, Please (Pause)
At times you may need to display some instructions to your user (like explaining
the rules of Hide and Go Tickle) and then wait for them to read those
instructions. For example, you might display the instructions followed by
“Press any key to continue . . . ” and then wait for the user to press a key
to show that they’re ready to continue. You can do this by using the Pause()
method.
To see this method in action, let’s write a program that converts the computer
into a wisdom machine. Each time the user presses a key, the computer
displays a new bit of wisdom. The program is shown in Listing 6-3.
1 ' WisdomMachine.sb
2 TextWindow.WriteLine("WISDOM OF THE DAY")
3
4 TextWindow.WriteLine("A friend in need is a friend indeed.")
76 Chapter 6