尝试读取或写入受保护的内存.这通常表明其他内存已损坏

Question

我使用以下代码

发生此错误:

尝试读取或写入受保护的内存.这通常表明其他内存已损坏.尝试读取或写入受保护的内存.这通常表明其他内存已损坏.

Public Class FormRegEnumValue

Private Const ERROR_SUCCESS = 0&
Private Const ERROR_NO_MORE_ITEMS = 259&
Private Const HKEY_CURRENT_USER = &H80000001

Private Const REG_BINARY = 3
Private Const REG_DWORD = 4
Private Const REG_EXPAND_SZ = 2
Private Const REG_SZ = 1

Private Declare Function RegEnumValue Lib "advapi32.dll" Alias "RegEnumValueA" (ByVal hKey As Long, ByVal dwIndex As Long, ByVal lpValueName As String, ByVal lpcbValueName As Long, ByVal lpReserved As Long, ByVal lpType As Long, ByVal lpData As Object, ByVal lpcbData 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, ByVal phkResult As Long) As Long


Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Dim hKey As Long, num As Long, strName As String
    Dim strData As String, Retval As Long, RetvalData As Long

    Const Buffer As Long = 255
    num = 0
    strName = Space(Buffer)
    strData = Space(Buffer)
    Retval = Buffer
    RetvalData = Buffer
    If RegOpenKey(HKEY_CURRENT_USER, "Control Panel\Desktop", hKey) = 0 Then 'error
        While RegEnumValue(hKey, num, strName, Retval, 0, 0&, strData, RetvalData) <> ERROR_NO_MORE_ITEMS
            If RetvalData > 0 Then
                ListBox1.Items.Add(strName + Retval + "  =  " + strData + RetvalData - 1)
            End If
            num = num + 1
            strName = Space(Buffer)
            strData = Space(Buffer)
            Retval = Buffer
            RetvalData = Buffer
        End While
        RegCloseKey(hKey)
    Else
        ListBox1.Items.Add("Error")
    End If
End Sub
End Class

请告诉我正确的方法

Answer 1

这通常是由不正确的Private Declare Function陈述引起的.Windows API中列出的类型与VB或C#代码中使用的类型不同.这是Windows API和.Net:Win32 API C++到.NET之间的数据类型转换的绝佳列表

该PInvoke的网站往往具有列出的正确VB代码.

对于RegEnumValue,修复数据类型,并且lpcValueName是ByRef,而不是ByVal:

Declare Auto Function RegEnumValue Lib "Advapi32" ( _
    ByVal hKey As IntPtr, _
    ByVal dwIndex As Integer, _
    ByVal lpValueName As StringBuilder, _
    ByRef lpcValueName As Integer, _
    ByVal lpReserved As IntPtr, _
    ByVal lpType As IntPtr, _
    ByVal lpData As IntPtr, _
    ByVal lpcbData As IntPtr _
) As Integer

对于RegCloseKey,只需修复数据类型:

Declare Function RegCloseKey Lib "advapi32.dll" ( _
    ByVal hKey As UIntPtr _
) As Integer

对于RegOpenKey,修复数据类型并将phkResult更改为ByRef:

Private Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" ( _
    ByVal hKey As Integer, _
    ByVal lpSubKey As String, _
    ByRef phkResult As IntPtr _
) As Integer

所以你的功能看起来应该更像这样.不幸的是,我不确定要写什么strData或者RetvalData.我添加了一个Try/Finally块,RegCloseKey即使发生错误也会确保被调用.你想确保你总是关闭事物,特别是如果出现问题.

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Const Buffer As Long = 255
    Dim hKey As IntPtr = IntPtr.Zero
    Dim num As Integer = 0
    Dim strName As New StringBuilder
    Dim strData As IntPtr = ' I'm not surte what goes here.
    Dim Retval As Integer = Buffer
    Dim RetvalData As IntPtr = ' I'm not surte what goes here.
    If RegOpenKey(HKEY_CURRENT_USER, "Control Panel\Desktop", hKey) = 0 Then 'error
        Try
            While RegEnumValue(hKey, num, strName, Retval, IntPtr.Zero, IntPtr.Zero, strData, RetvalData) <> ERROR_NO_MORE_ITEMS
                If RetvalData > 0 Then
                    ListBox1.Items.Add(strName.ToString + Retval + "  =  " + strData + RetvalData - 1)
                End If
                num = num + 1
                strName = New StringBuilder(Buffer)
                strData = ' I'm not sure what goes here.
                Retval = Buffer
                RetvalData = ' I'm not surte what goes here.
            End While
        Finally
            RegCloseKey(hKey)
        End Try
    Else
        ListBox1.Items.Add("Error")
    End If
End Sub