Zoom-In & Zoom-Out

[Ramandeep]

CAn any one show me by example how I may use the Plus ('+') & minus ('-') keys on the key pad to soom into & out of a picture in a picture box.

Keeping the image in proportion, like you didn't know that

Thanks in advance!!

Ram

If you place your picture in an ImageBox you can use this code.

Put this in the KeyDown event of the Form.


Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)

If KeyCode = vbKeyAdd Then
Image1.Stretch = True
Image1.Width = Image1.Width * 2
Image1.Height = Image1.Height * 2
End If

If KeyCode = vbKeySubtract Then
Image1.Stretch = True
Image1.Width = Image1.Width / 2
Image1.Height = Image1.Height / 2
End If

End Sub


Private Sub Form_Load()

Me.KeyPreview = True
Image1.Stretch = True

End Sub

[kedaman]

Without replacing it with a Imagebox you could use this code:

Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
Dim speed As Integer

Select Case Chr(KeyCode)
Case "-"
speed = 10
Case "+"
speed = -10
Case Else
Exit Sub
End Select

With Picture1
.Picture = .Image
.PaintPicture Picture1, 0, 0, .ScaleWidth, .ScaleHeight, .ScaleWidth / speed, .ScaleHeight / speed, .ScaleWidth - .ScaleWidth / speed * 2, .ScaleHeight - .ScaleHeight / speed * 2
End With

End Sub

justify speed for your needs ;)

Here is another way that is keeping the PictureBox. For this, you need to create 2 PictureBoxes. Load your Picture into Picture2.


Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)


If KeyCode = vbKeyAdd Then
With Picture1
.Cls
.Width = .Width * 2
.Height = .Height * 2
.PaintPicture Picture2.Picture, 0, 0, .ScaleWidth, .ScaleHeight
End With
End If


If KeyCode = vbKeySubtract Then
With Picture1
.Cls
.Width = .Width / 2
.Height = .Height / 2
.PaintPicture Picture2.Picture, 0, 0, .ScaleWidth, .ScaleHeight
End With
End If


End Sub

Private Sub Form_Load()

Picture2.Visible = False
Me.KeyPreview = True
Picture1.AutoRedraw = True
Picture1.PaintPicture Picture2.Picture, 0, 0

End Sub