Practice Exercise 4
Looping

Write a program that prints the following patterns separately on the form each time a button is pressed.  Provide four buttons A, B, C and D.  When button A is pressed, the triangle shown in part (A) is printed, etc.  Use For/Next loops to generate the patterns.  Each triangle's asterisks (*) should be printed by a single statement; (this causes the asterisks to print side by side).  A vbCrLf (vb Carriage Return/Line Feed) will move the cursor to the next line.  Use a label to display your output.

Hints:

The last two patterns require that each line begin with an appropriate number of blanks.  You can use the Space(someNum) to generate a String containing spaces. The value passed to Space specifies the number of spaces to create.  Use nested For/Next structures and minimize the number of output statements.

(A) (B) (C) (D)
*
**
***
****
*****
******
*******
********
*********
**********
**********
*********
********
*******
******
*****
****
***
**
*
**********
 *********
  ********
   *******
    ******
     *****
      ****
       ***
        **
         *
         *
        **
       ***
      ****
     *****
    ******
   *******
  ********
 *********
**********

Here is a demo if you need it.

Here is an example of a possible interface.


Solution

sln File