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一些简单的编程例子 都是网页的形式

<p>怎样用VB得知系统当前是否处于internet链结状态</p>
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<p>声明以下函数变量常量：</p>
<p>Declare Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As Long</p>
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<p>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</p>
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<p>Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult As Long) As Long</p>
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<p>Public Const ERROR_SUCCESS = 0&</p>
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<p>Public Const APINULL = 0&</p>
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<p>Public Const HKEY_LOCAL_MACHINE = &H80000002</p>
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<p>Public ReturnCode As Long</p>
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<p>代码：</p>
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<p>Public Function ActiveConnection() As Boolean</p>
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<p>Dim hKey As Long</p>
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<p>Dim lpSubKey As String</p>
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<p>Dim phkResult As Long</p>
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<p>Dim lpValueName As String</p>
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<p>Dim lpReserved As Long</p>
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<p>Dim lpType As Long</p>
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<p>Dim lpData As Long</p>
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<p>Dim lpcbData As Long</p>
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<p>ActiveConnection = False</p>
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<p>lpSubKey = "System\CurrentControlSet\Services\RemoteAccess"</p>
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<p>ReturnCode = RegOpenKey(HKEY_LOCAL_MACHINE, lpSubKey, phkResult)</p>
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<p>If ReturnCode = ERROR_SUCCESS Then</p>
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<p>hKey = phkResult</p>
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<p>lpValueName = "Remote Connection"</p>
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<p>lpReserved = APINULL</p>
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<p>lpType = APINULL</p>
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<p>lpData = APINULL</p>
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<p>lpcbData = APINULL</p>
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<p>ReturnCode = RegQueryValueEx(hKey, lpValueName, lpReserved, lpType, lpData, lpcbData)</p>
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<p>lpcbData = Len(lpData)</p>
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<p>ReturnCode = ReturnCode = RegQueryValueEx(hKey, lpValueName, lpReserved, lpType, lpData, lpcbData)</p>
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<p>If ReturnCode = ERROR_SUCCESS Then</p>
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<p>If lpData = 0 Then</p>
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<p>ActiveConnection = False</p>
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<p>Else</p>
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<p>ActiveConnection = True</p>
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<p>End If</p>
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<p>End If</p>
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<p>RegCloseKey (hKey)</p>
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<p>End If</p>
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<p>End Function</p>
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<p>下面是使用以上代码的例子：</p>
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<p>If ActiveConnection = True then</p>
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<p>Call MsgBox("现在处于链结状态。",vbInformation)</p>
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<p>Else</p>
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<p>Call MsgBox("现在处于断开状态。", vbInformation)</p>
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<p>End If</p>
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