using?System;
using?System.Runtime.InteropServices;
public?struct?RASCONN
{
public?int?dwSize;
public?IntPtr?hrasconn;
[MarshalAs（UnmanagedType.ByValTStr?SizeConst=257）]
public?string?szEntryName;
[MarshalAs（UnmanagedType.ByValTStr?SizeConst=17）]
public?string?szDeviceType;
[MarshalAs（UnmanagedType.ByValTStr?SizeConst=129）]
public?string?szDeviceName;
}

[StructLayout（LayoutKind.SequentialCharSet=CharSet.Auto）]
public?struct?RasStats
{
public?int?dwSize;
public?int?dwBytesXmited;
public?int?dwBytesRcved;
public?int?dwframesXmited;
public?int?dwframesRcved;
public?int?dwCrcErr;
public?int?dwTimeoutErr;
public?int?dwAlignmentErr;
public?int?dwHardwareOverrunErr;
public?int?dwFramingErr;
public?int?dwBufferOverrunErr;
public?int?dwCompressionRatioIn;
public?int?dwCompressionRatioOut;
public?int?dwBps;
public?int?dwConnectionDuration;
}

[StructLayout（LayoutKind.SequentialCharSet=CharSet.Auto）]
public?struct?RasEntryName
{
public?int?dwSize;
//[Ma