设置窗体背景图片，并且让图片随着窗体的大小的调整而调整大小

Private r As RectangleF

Private m_image As Image = Image.FromFile("g:/picture.bmp")

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Try
r = New RectangleF(0, 0, Me.ClientSize.Width, Me.ClientSize.Height)
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub

Private Sub mydrawimage()
Try
Dim g As Graphics = Me.CreateGraphics
g.DrawImage(m_image, r)
g.Dispose()
Catch ex As Exception

End Try
End Sub
Private Sub Form1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint

mydrawimage()

End Sub

Private Sub Form1_Resize(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Resize

r = New RectangleF(0, 0, Me.ClientSize.Width, Me.ClientSize.Height)

mydrawimage()
End Sub