怎样使DataGrid支持鼠标滚轮滚动记录

在本站的VB源码《数据网格下拉列表框控件》中(链接地址：http://www.mndsoft.com/blog/article.asp?id=214)中，网友 taomaintao 提示支持滚轮鼠标，其实原本代码有已经有部分API代码意图支持鼠标滚轮，但可能作者后来没有加上。基于此，我找到一个解决办法（来自网络），taomaintao 网友可以按照下面自己进行修改吧。

首先在DataGrid 的 【拆分】 属性中的【选取框样式】设置为 3，即整行高亮选择，然后加入如下代码就支持了，只要让鼠标的焦点在grid控件上，滚动鼠标滑轮，grid滚动条会自动滚动的。

如果需要更平滑的滚动以及自定义滚动方法，我还有个代码，到时发给你，你自己研究吧。

示例操作方法：
将以下代码写到公共模块中

'支持滚轮鼠标API---------------------------------
Public Const GWL_WNDPROC = (-4)
Public Const WM_COMMAND = &H111
Public Const WM_MBUTTONDOWN = &H207
Public Const WM_MBUTTONUP = &H208
Public Const WM_MOUSEWHEEL = &H20A

Public Oldwinproc As Long
Public Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hWnd As Long, _
ByVal nIndex As Long, ByVal dwNewLong As Long) As Long

Public Declare Function CallWindowProc Lib "user32" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Long, _
ByVal hWnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long

Public Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hWnd As Long, _
ByVal nIndex As Long) As Long
Public Function FlexScroll(ByVal hWnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
'支持滚轮的滚动 Yu 2004-5-10 15:33
Select Case wMsg
Case WM_MOUSEWHEEL
Select Case wParam
Case -7864320 '向下滚
SendKeys "{PGDN}"
Case 7864320 '向上滚
SendKeys "{PGUP}"
End Select

End Select
FlexScroll = CallWindowProc(Oldwinproc, hWnd, wMsg, wParam, lParam)
End Function
'支持滚轮鼠标API---------------------------------

'将下列代码写到表格控件的GotFocus事件中
Private Sub 控件名称_GotFocus()
Oldwinproc = GetWindowLong(Me.hWnd, GWL_WNDPROC)
SetWindowLong Me.hWnd, GWL_WNDPROC, AddressOf FlexScroll
End Sub

'将下列代码写到表格控件的LostFocus事件中
Private Sub 控件名称_LostFocus()
SetWindowLong Me.hWnd, GWL_WNDPROC, Oldwinproc
End Sub