VB检查合法IP地址

Public Function IsValidIPAddress(ByVal strIPAddress As String) As Boolean
    On Error GoTo Handler
    Dim varAddress As Variant, n As Long, lCount As Long
    varAddress = Split(strIPAddress, ".", , vbTextCompare)
    If IsArray(varAddress) Then
        For n = LBound(varAddress) To UBound(varAddress)
            lCount = lCount + 1
            varAddress(n) = CByte(varAddress(n))
        Next
        IsValidIPAddress = (lCount = 4)
    Else
        IsValidIPAddress = False
    End If
Handler:
End Function