计算机等级考试二级VB：VB中实现菜单分割

　　在VB中要实现这一功能还是比较方便的，下面举例说明。

　　实现菜单分割这一功能需要使用API函数，思路是：首先获得菜单句柄，从而可得到其子菜单项数，然后将子菜单项数除以2,若子菜单项数为奇数，则将多余的一项划到第一部分，然后利用API函数SetMenuItemInfo重新设定菜单显示形式即可。

　　下面是一个例子。首先用菜单生成器制做一个包括9个子菜单项的菜单，然后，在总体声明部分声明用到的API函数和常数，这些可以从API说明文件中复制。

　　Option Explicit

　　′菜单信息结构说明

　　Private Type MENUITEMINFO

　　cbSize As Long

　　fMask As Long

　　fType As Long

　　fState As Long

　　wID As Long

　　hSubMenu As Long

　　hbmpChecked As Long

　　hbmpUnchecked As Long

　　dwItemData As Long

　　dwTypeData As String

　　cch As Long

　　End Type

　　'所需的API函数和常数

　　Private Declare Function GetMenu Lib "user32" (ByVal hwnd As Long) As Long

　　Private Declare Function GetMenuItemCount Lib "user32" (ByVal hMenu As Long) _

　　As Long

　　Private Declare Function GetSubMenu Lib "user32" (ByVal hMenu As Long, _

　　ByVal nPos As Long) As Long

　　Private Declare Function GetMenuItemInfo Lib "user32" Alias _

　　"GetMenuItemInfoA" (ByVal hMenu As Long, ByVal un As Long, _

　　ByVal b As Boolean, lpmii As MENUITEMINFO) As Long

　　Private Declare Function SetMenuItemInfo Lib "user32" Alias _

　　"SetMenuItemInfoA" (ByVal hMenu As Long, ByVal uItem As Long, _

　　ByVal fByPosition As Long, lpmii As MENUITEMINFO) As Long

　　Const MIIM_TYPE = &H10

　　Const RGB_STARTNEWCOLUMNWITHVERTBAR = &H20&

　　Const MFT_STRING = &H0&

　　在窗体中添加一个命令按钮，Caption=“分割菜单”，双击写如下代码：

　　Private Sub Command1_Click()

　　Dim rv As Long

　　Dim hSubMenu As Long

　　Dim mnuItemCount As Long

　　Dim mInfo As MENUITEMINFO

　　Dim pad As Long

　　'获取菜单项句柄和子菜单项数

　　hSubMenu=GetSubMenu(GetMenu(Me.hwnd), 0)

　　mnuItemCount=GetMenuItemCount(hSubMenu)

　　'将子菜单项分成两部分

　　If mnuItemCount Mod 2<>0 Then pad=1

　　'取得当前菜单信息

　　mInfo.cbSize=Len(mInfo)

　　mInfo.fMask=MIIM_TYPE

　　mInfo.fType=MFT_STRING

　　mInfo.dwTypeData=Space$(256)

　　mInfo.cch=Len(mInfo.dwTypeData)

　　rv=GetMenuItemInfo(hSubMenu, (mnuItemCount\2)+pad, True, mInfo)

　　'按新格式显示菜单

　　mInfo.fType=RGB_STARTNEWCOLUMNWITHVERTBAR

　　mInfo.fMask=MIIM_TYPE

　　rv=SetMenuItemInfo(hSubMenu, (mnuItemCount\2)+pad, True, mInfo)

　　If rv Then MsgBox "分割完毕"

　　End Sub

　　运行后按命令按钮，将发现子菜单项分成了两部分，左边五项，右边四项。

　　程序运行环境：中文WIN95，VB 5.0。