拨号、断网、枚举连接名称，判断是否在线、连接方式

Option Explicit
'拨号/断网
Private Declare Function InternetDial Lib "wininet.dll" (ByVal hwndParent As Long, ByVal lpszConnectoid As String, ByVal dwFlags As Long, lpdwConnection As Long, ByVal dwReserved As Long) As Long
Private Declare Function InternetHangUp Lib "wininet.dll" (ByVal dwConnection As Long, ByVal dwReserved As Long) As Long
Private Declare Function InternetAutodial Lib "wininet.dll" (ByVal dwFlags As Long, ByVal dwReserved As Long) As Long
Private Declare Function InternetAutodialHangup Lib "wininet.dll" (ByVal dwReserved As Long) As Long
Private Const INTERNET_DIALSTATE_DISCONNECTED = 1
Private Const INTERNET_AUTODIAL_FORCE_ONLINE = 1
Private Const INTERNET_AUTODIAL_FORCE_UNATTENDED = 2
Private Const INTERNET_DIAL_UNATTENDED = &H8000
Private Handle As Long

'网络状态
Private Declare Function InternetGetConnectedStateEx Lib "wininet.dll" Alias "InternetGetConnectedStateExA" (ByRef lpdwFlags As Long, ByVal lpszConnectionName As String, ByVal dwNameLen As Long, ByVal dwReserved As Long) As Long
Private Declare Function InternetGetConnectedState Lib "wininet.dll" (ByRef dwFlags As Long, ByVal dwReserved As Long) As Long
Private Const INTERNET_CONNECTION_MODEM As Long = &H1      '本系统使用调制解调器与因特网相连
Private Const INTERNET_CONNECTION_LAN As Long = &H2        '本系统通过LAN与因特网相连
Private Const INTERNET_CONNECTION_PROXY As Long = &H4      '本系统使用proxy代理服务器与因特网相连
Private Const INTERNET_CONNECTION_MODEM_BUSY As Long = &H8 '未使用
Private Const INTERNET_RAS_INSTALLED As Long = &H10
Private Const INTERNET_CONNECTION_OFFLINE As Long = &H20
Private Const INTERNET_CONNECTION_CONFIGURED As Long = &H40

'枚举网络连接
Private Const RAS_MaxDeviceType = 16
Private Const RAS95_MaxDeviceName = 128
Private Const RAS95_MaxEntryName = 256
Private Type RASCONN95
    dwSize As Long
    hRasConn As Long
    szEntryName(RAS95_MaxEntryName) As Byte
    szDeviceType(RAS_MaxDeviceType) As Byte
    szDeviceName(RAS95_MaxDeviceName) As Byte
End Type
Private Type RASENTRYNAME95
    dwSize As Long
    szEntryName(RAS95_MaxEntryName) As Byte
End Type
Private Declare Function RasEnumConnections Lib "rasapi32.dll" Alias "RasEnumConnectionsA" (lprasconn As Any, lpcb As Long, lpcConnections As Long) As Long
Private Declare Function RasEnumEntries Lib "rasapi32.dll" Alias "RasEnumEntriesA" (ByVal reserved As String, ByVal lpszPhonebook As String, lprasentryname As Any, lpcb As Long, lpcEntries As Long) As Long
Private Declare Function RasHangUp Lib "rasapi32.dll" Alias "RasHangUpA" (ByVal hRasConn As Long) As Long

'拨号
Public Function DialUp(LinkName As String) As Boolean
    InternetDial 0, LinkName, INTERNET_AUTODIAL_FORCE_UNATTENDED, Handle, 0
    DialUp = (Handle <> 0)
End Function
'断网
Public Sub HangUp()
    If Handle <> 0 Then
        InternetHangUp Handle, 0
        Handle = 0
    End If
End Sub

'枚举网络连接
Public Sub EnumConnectName(Value() As String)
    Dim s As Long, l As Long, ln As Long, a As String
    ReDim r(255) As RASENTRYNAME95

    r(0).dwSize = 264
    s = 256 * r(0).dwSize
    l = RasEnumEntries(vbNullString, vbNullString, r(0), s, ln)
    ReDim Value(ln - 1)
    For l = 0 To ln - 1
        a = StrConv(r(l).szEntryName(), vbUnicode)
        Value(l) = Left$(a$, InStr(a$, Chr$(0)) - 1)
    Next
End Sub

'判断是否在线
Public Function Online() As Boolean
    Online = InternetGetConnectedState(0&, 0&)
End Function
'判断是否在线并返回连接方式
Public Property Get OnlineOfLinkName(LinkName As String) As Boolean
    LinkName = Space$(128)
    OnlineOfLinkName = InternetGetConnectedStateEx(0, LinkName, 128, 0&)
End Property

'如果是通过LAN的连接，则返回True
Public Function IsNetConnectViaLAN() As Boolean
    Dim dwFlags As Long
    Call InternetGetConnectedState(dwFlags, 0&)
    IsNetConnectViaLAN = dwFlags And INTERNET_CONNECTION_LAN
End Function
'如果是通过调制解调器的连接，则返回True
Public Function IsNetConnectViaModem() As Boolean
    Dim dwFlags As Long
    Call InternetGetConnectedState(dwFlags, 0&)
    IsNetConnectViaModem = dwFlags And INTERNET_CONNECTION_MODEM
End Function
'如果是通过Proxy代理服务器的连接，则返回True
Public Function IsNetConnectViaProxy() As Boolean
    Dim dwFlags As Long
    Call InternetGetConnectedState(dwFlags, 0&)
    IsNetConnectViaProxy = dwFlags And INTERNET_CONNECTION_PROXY
End Function
'如果已安装了RAS，则返回True
Public Function IsNetRASInstalled() As Boolean
    Dim dwFlags As Long
    Call InternetGetConnectedState(dwFlags, 0&)
    IsNetRASInstalled = dwFlags And INTERNET_RAS_INSTALLED
End Function
'返回当前网络状态信息字符串
Public Function GetNetConnectString() As String
    Dim dwFlags As Long
    Dim msg As String
    If InternetGetConnectedState(dwFlags, 0&) Then
        If dwFlags And INTERNET_CONNECTION_CONFIGURED Then
            msg = msg & "系统配置了网络连接" & vbCrLf
        End If
        If dwFlags And INTERNET_CONNECTION_LAN Then
            msg = msg & "系统通过局域网与因特网相连接"
        End If
        If dwFlags And INTERNET_CONNECTION_PROXY Then
            msg = msg & "并使用了Proxy代理服务"
        Else: msg = msg & "."
        End If
        If dwFlags And INTERNET_CONNECTION_MODEM Then
            msg = msg & "系统使用调制解调器与因特网相连接"
        End If
        If dwFlags And INTERNET_CONNECTION_OFFLINE Then
            msg = msg & "系统当前处于离线状态"
        End If
        If dwFlags And INTERNET_CONNECTION_MODEM_BUSY Then
            msg = msg & "系统的调制解调器未连接到因特网"
        End If
        If dwFlags And INTERNET_RAS_INSTALLED Then
            msg = msg & "本系统安装了远程访问服务"
        End If
    Else
        msg = "当前未与因特网相连"
    End If
    GetNetConnectString = msg
End Function