Visual Basic Reference
ScaleLeft, ScaleTop Properties Example
This example creates a grid in a PictureBox control and sets coordinates for the upper-left corner to -1, -1 instead of 0, 0. Every 0.25 second, dots are randomly plotted from the upper-left corner to the lower-right corner. To try this example, paste the code into the Declarations section of a form that contains a large PictureBox and a Timer control, and then press F5.
Private Sub Form_Load ()
Timer1.Interval = 250 ' Set Timer interval.
Picture1.ScaleTop = -1 ' Set scale for top of grid.
Picture1.ScaleLeft = -1 ' Set scale for left of grid.
Picture1.ScaleWidth = 2 ' Set scale (-1 to 1).
Picture1.ScaleHeight = 2
Picture1.Line (-1, 0)-(1, 0) ' Draw horizontal line.
Picture1.Line (0, -1)-(0, 1) ' Draw vertical line.
End Sub
Private Sub Timer1_Timer ()
Dim I ' Declare variable.
' Plot dots randomly within a range.
For I = -1 To 1 Step .05
Picture1.PSet (I * Rnd, I * Rnd) ' Draw a point.
Next I
End Sub