VB.NET:
Private Sub ZoomInToolStripMenuItem_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ZoomInToolStripMenuItem.Click
PictureBox1.Width = CInt(PictureBox1.Width * 1.25)
PictureBox1.Height = CInt(PictureBox1.Height * 1.25)
PictureBox1.SizeMode = PictureBoxSizeMode.Zoom
End Sub
Thanks !!!