如何利用vb实现像按键精灵的功能？

用API函数来做。
Timer事件引发时，先用SetCursorPos函数设置鼠标位置（你所要指定的位置），然后用mouse_event函数引发Mouse点击事件（MOUSEEVENTF_LEFTDOWN Or MOUSEEVENTF_LEFTUP）。

API函数声明及常量如下：

'设置鼠标位置
Private Declare Function SetCursorPos Lib "user32" (ByVal X As Long, ByVal Y As Long) As Long
'获取鼠标位置
Private Declare Function GetCursorPos Lib "user32" (lpPoint As POINTAPI) As Long
'鼠标事件
Private Declare Sub mouse_event Lib "user32" (ByVal dwFlags As Long, ByVal dx As Long, ByVal dy As Long, ByVal cButtons As Long, ByVal dwExtraInfo As Long)

'常量
Private Const MOUSEEVENTF_MOVE = &H1 ' mouse move
Private Const MOUSEEVENTF_LEFTDOWN = &H2 ' left button down
Private Const MOUSEEVENTF_LEFTUP = &H4 ' left button up
Private Const MOUSEEVENTF_RIGHTDOWN = &H8 ' right button down
Private Const MOUSEEVENTF_RIGHTUP = &H10 ' right button up