VB的寫法，關於版本寫入註冊表

時間 2019-11-11

原文原文鏈接

'軟件都有一個關於咱們的菜單，單單實現這個功能並不難，困難的是可以將這些信息寫入註冊表中，這樣每次只要彈出這樣的窗口，就從註冊表裏去搜索。這樣是否是極大的節省了資源。
這裏也是一種通用的用法，例子比較初級。下面是所有的代碼：
Option Explicit

' 註冊表關鍵字安全選項...
Const READ_CONTROL = &H20000
Const KEY_QUERY_VALUE = &H1
Const KEY_SET_VALUE = &H2
Const KEY_CREATE_SUB_KEY = &H4
Const KEY_ENUMERATE_SUB_KEYS = &H8
Const KEY_NOTIFY = &H10
Const KEY_CREATE_LINK = &H20
Const KEY_ALL_ACCESS = KEY_QUERY_VALUE + KEY_SET_VALUE + _
                       KEY_CREATE_SUB_KEY + KEY_ENUMERATE_SUB_KEYS + _
                       KEY_NOTIFY + KEY_CREATE_LINK + READ_CONTROL
                     
' 註冊表關鍵字 ROOT 類型...
Const HKEY_LOCAL_MACHINE = &H80000002
Const ERROR_SUCCESS = 0
Const REG_SZ = 1                         ' 獨立的空的終結字符串
Const REG_DWORD = 4                      ' 32位數字

Const gREGKEYSYSINFOLOC = "SOFTWARE\Microsoft\Shared Tools Location"
Const gREGVALSYSINFOLOC = "MSINFO"
Const gREGKEYSYSINFO = "SOFTWARE\Microsoft\Shared Tools\MSINFO"
Const gREGVALSYSINFO = "PATH"

Private Declare Function RegOpenKeyEx Lib "advapi32" Alias "RegOpenKeyExA" (ByVal hKey As Long, ByVal lpSubKey As String, ByVal ulOptions As Long, ByVal samDesired As Long, ByRef phkResult As Long) As Long
Private Declare Function RegQueryValueEx Lib "advapi32" Alias "RegQueryValueExA" (ByVal hKey As Long, ByVal lpValueName As String, ByVal lpReserved As Long, ByRef lpType As Long, ByVal lpData As String, ByRef lpcbData As Long) As Long
Private Declare Function RegCloseKey Lib "advapi32" (ByVal hKey As Long) As Long


Private Sub cmdSysInfo_Click()
  Call StartSysInfo
End Sub

Private Sub cmdOK_Click()
  Unload Me
End Sub

Private Sub Form_Load()
On Error Resume Next
    Me.Caption = GetLang("lang_abbout_title")
    lblVersion.Caption = GetLang("lang_version") & App.Major & "." & App.Minor & "." & App.Revision
    lblTitle.Caption = GetLang("lang_appname")
    ImageLogo.Picture = LoadPicture(App.Path & "\logo.jpg")
    cmdOK.Caption = GetLang("lang_confirm")
    lblDescription.Caption = GetLang("lang_lblDescription")
    lblContact.Caption = GetLang("lang_lblContact")
End Sub

Public Sub StartSysInfo()
    On Error GoTo SysInfoErr
  
    Dim rc As Long
    Dim SysInfoPath As String
    
    ' 試圖從註冊表中得到系統信息程序的路徑及名稱...
    If GetKeyValue(HKEY_LOCAL_MACHINE, gREGKEYSYSINFO, gREGVALSYSINFO, SysInfoPath) Then
    ' 試圖僅從註冊表中得到系統信息程序的路徑...
    ElseIf GetKeyValue(HKEY_LOCAL_MACHINE, gREGKEYSYSINFOLOC, gREGVALSYSINFOLOC, SysInfoPath) Then
        ' 已知32位文件版本的有效位置
        If (Dir(SysInfoPath & "\MSINFO32.EXE") <> "") Then
            SysInfoPath = SysInfoPath & "\MSINFO32.EXE"
            
        ' 錯誤 - 文件不能被找到...
        Else
            GoTo SysInfoErr
        End If
    ' 錯誤 - 註冊表相應條目不能被找到...
    Else
        GoTo SysInfoErr
    End If
    
    Call Shell(SysInfoPath, vbNormalFocus)
    
    Exit Sub
SysInfoErr:
   ' MsgBox "此時系統信息不可用", vbOKOnly
End Sub

Public Function GetKeyValue(KeyRoot As Long, KeyName As String, SubKeyRef As String, ByRef KeyVal As String) As Boolean
    Dim i As Long                                           ' 循環計數器
    Dim rc As Long                                          ' 返回代碼
    Dim hKey As Long                                        ' 打開的註冊表關鍵字句柄
    Dim hDepth As Long                                      '
    Dim KeyValType As Long                                  ' 註冊表關鍵字數據類型
    Dim tmpVal As String                                    ' 註冊表關鍵字值的臨時存儲器
    Dim KeyValSize As Long                                  ' 註冊表關鍵自變量的尺寸
    '------------------------------------------------------------
    ' 打開 {HKEY_LOCAL_MACHINE...} 下的 RegKey
    '------------------------------------------------------------
    rc = RegOpenKeyEx(KeyRoot, KeyName, 0, KEY_ALL_ACCESS, hKey) ' 打開註冊表關鍵字
    
    If (rc <> ERROR_SUCCESS) Then GoTo GetKeyError          ' 處理錯誤...
    
    tmpVal = String$(1024, 0)                             ' 分配變量空間
    KeyValSize = 1024                                       ' 標記變量尺寸
    
    '------------------------------------------------------------
    ' 檢索註冊表關鍵字的值...
    '------------------------------------------------------------
    rc = RegQueryValueEx(hKey, SubKeyRef, 0, _
                         KeyValType, tmpVal, KeyValSize)    ' 得到/建立關鍵字值
                        
    If (rc <> ERROR_SUCCESS) Then GoTo GetKeyError          ' 處理錯誤
    
    If (Asc(Mid(tmpVal, KeyValSize, 1)) = 0) Then           ' Win95 外接程序空終結字符串...
        tmpVal = Left(tmpVal, KeyValSize - 1)               ' Null 被找到,從字符串中分離出來
    Else                                                    ' WinNT 沒有空終結字符串...
        tmpVal = Left(tmpVal, KeyValSize)                   ' Null 沒有被找到, 分離字符串
    End If
    '------------------------------------------------------------
    ' 決定轉換的關鍵字的值類型...
    '------------------------------------------------------------
    Select Case KeyValType                                  ' 搜索數據類型...
    Case REG_SZ                                             ' 字符串註冊關鍵字數據類型
        KeyVal = tmpVal                                     ' 複製字符串的值
    Case REG_DWORD                                          ' 四字節的註冊表關鍵字數據類型
        For i = Len(tmpVal) To 1 Step -1                    ' 將每位進行轉換
            KeyVal = KeyVal + hex(Asc(Mid(tmpVal, i, 1)))   ' 生成值字符。 By Char。
        Next
        KeyVal = Format$("&h" + KeyVal)                     ' 轉換四字節的字符爲字符串
    End Select
    
    GetKeyValue = True                                      ' 返回成功
    rc = RegCloseKey(hKey)                                  ' 關閉註冊表關鍵字
    Exit Function                                           ' 退出
    
GetKeyError:      ' 錯誤發生後將其清除...
    KeyVal = ""                                             ' 設置返回值到空字符串
    GetKeyValue = False                                     ' 返回失敗
    rc = RegCloseKey(hKey)                                  ' 關閉註冊表關鍵字
End Function