贴上源码

程序代码:
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Button1.BackgroundImage = My.Resources.a
End Sub
Private Sub Button1_MouseLeave(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.MouseLeave
Button1.BackgroundImage = My.Resources.a
End Sub
Private Sub Button1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Button1.MouseMove
Button1.BackgroundImage = My.Resources.b
End Sub
End Class