求高人啊！！！为什么vb API写入DWORD时0总是变成30就是变成了ASCII码
本帖最后由 qq363466330 于 2011-09-19 19:19:38 编辑 Private Const HKEY_CURRENT_USER = &H80000001
Private Const HKEY_LOCAL_MACHINE = &H80000002
Private Const HKEY_CLASSES_ROOT = &H80000000
Private Const HKEY_CURRENT_CONFIG = &H80000005
Private Const HKEY_USERS = &H80000003
Private Declare Function RegEnumValue Lib "advapi32.dll" Alias "RegEnumValueA" (ByVal hKey As Long, ByVal dwIndex As Long, ByVal lpValueName As String, lpcbValueName As Long, lpReserved As Long, lpType As Long, lpData As Byte, lpcbData As Long) As Long
Private Declare Function RegCreateKey Lib "advapi32.dll" Alias "RegCreateKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult As Long) As Long
Private Declare Function RegOpenKeyEx Lib "advapi32.dll" Alias "RegOpenKeyExA" (ByVal hKey As Long, ByVal lpSubKey As String, ByVal ulOptions As Long, ByVal samDesired As Long, phkResult As Long) As Long
Private Declare Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As Long
Private Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult As Long) As Long
Private Declare Function RegQueryValueEx Lib "advapi32.dll" Alias "RegQueryValueExA" (ByVal hKey As Long, ByVal lpValueName As String, ByVal lpReserved As Long, lpType As Long, lpData As Any, lpcbData As Long) As Long
Private Declare Function RegSetValueEx Lib "advapi32.dll" Alias "RegSetValueExA" (ByVal hKey As Long, ByVal lpValueName As String, ByVal Reserved As Long, ByVal dwType As Long, ByVal lpData As String, ByVal cbData As Long) As Long
Private Declare Function RegSetValueExA Lib "advapi32.dll" (ByVal hKey As Long, ByVal lpValueName As String, ByVal Reserved As Long, ByVal dwType As Long, ByRef lpData As Long, ByVal cbData As Long) As Long
Private Declare Function RegDeleteKey Lib "advapi32.dll" Alias "RegDeleteKeyA" (ByVal hKey As Long, ByVal lpSubKey As String) As Long
Private Declare Function RegDeletevalue Lib "advapi32.dll" Alias "RegDeleteValueA" (ByVal hKey As Long, ByVal lpValueName As String) As Long
Private Declare Function RegSaveKey Lib "advapi32.dll" Alias "RegSaveKeyA" (ByVal hKey As Long, ByVal lpFile As String, ByVal lpSecurityAttributes As Long) As Long
Private Declare Function RegRestoreKey Lib "advapi32.dll" Alias "RegRestoreKeyA" (ByVal hKey As Long, ByVal lpFile As String, ByVal dwFlags As Long) As Long
Private Const REG_DWORD = 4
Private Sub Form_Load()
Dim rtn As Long
RegOpenKey HKEY_CURRENT_USER, "Software\Microsoft\Windows\CurrentVersion\Policies\system", rtn
RegSetValueEx rtn, "DisableChangePassword", 0, REG_DWORD, ByVal 0, 4
End Sub
就是这个SetValueEx 后 0 总是变成了它的ASCII码，那该如何将值赋为 0 呢？
[解决办法]
Private Declare Function RegSetValueEx Lib "advapi32.dll" Alias "RegSetValueExA" (ByVal hKey As Long, ByVal lpValueName As String, ByVal Reserved As Long, ByVal dwType As Long, ByVal lpData As String, ByVal cbData As Long) As Long
你倒数第二个参数声明的是string，当然传进去的时候会变成字符
[解决办法]
1L正解
调用API时，VB编译器会对String类型数据进行转换，首先会将相应类型转换为string，然后将unicode转换为ansi编码，再将转换后的指针传递给API
