1. For loops intCount = 1 inCount = intCount + 1 True intCount
For intCount = 1 To 5
Me.CreateGraphics.DrawEllipse(objPen, _
0, intYCoord, 50, 50)
intYCoord += 110
Next intCount
intCount = 1
inCount = intCount + 1
Draw circle
True
intCount
<= 5
False
Draws 5 circles

2. For loops Numeric Anything that variable has a numeric value
For Index = InitialValue To TestValue _
Step Increment
statements
Next Index
Optional
If omitted, the
increment is 1
Can just write Next
But clearer to write Next Index

3. For loops For Index = InitialValue To TestValue _ Step Increment
statements
Next Index
index = InitialValue
index = index + Increment
statements
True
index <=,>=
TestValue
if Increment > 0
if Increment < 0
False

4. Counting in For loops We can print a line of 5 circles: OOOOO
How would you print?
OOOOO
use:
repeat 5 times
‘Changing X coordinates
Me.CreateGraphics.DrawEllipse
(objPen, intXCoord, intYCoord, _
50, 50)
repeat 3 times
‘Changing Y coordinates
Nested For loops

5. In VB inner loop: print one row of 5 circles outer loop: once a line
' Create a Pen object.
Dim objPen As New Pen(Color.Red, 1)
Dim intNumCols, intNumRows, intInnerCounter, _
intOuterCounter, intXCoord, intYCoord As Integer
intNumCols = 5
intNumRows = 3
For intOuterCounter = 1 To intNumRows
For intInnerCounter = 1 To intNumCols
Me.CreateGraphics.DrawEllipse(objPen, _
intXCoord, intYCoord, 100, 100)
intXCoord += 110 ‘update X coordinates
Next intInnerCounter
intXCoord = 0 ‘reset X coordinates
intYCoord += 110 ‘update Y coords to move down
Next intOuterCounter
inner loop: print one row of 5 circles
outer loop: once a line
of 5 circles is printed,
Increase Y coordinates
All of this 3 times

6. Loop Pitfalls For intCount = 1 To 10 Step 2 intCount = 1 Next intCount
Get a never
ending loop
What happens?
intFinal = 10
For intCount = 1 To intFinal
intFinal = -5
Me.CreateGraphics.DrawEllipse(pen, _
0, intYCoord, 50, 50)
Next intCount
VB doesn't
take into account
the modification
for the loop counting
The loop is executed
10 times
What happens?
In a loop, don't change the values of
the variables used for the counting