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.Sequential, CharSet = 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.Sequential, CharSet = CharSet.Auto)]
public struct RasEntryName

{
public int dwSize;
//[MarshalAs(UnmanagedType.ByValTStr,SizeConst=(int)RasFieldSizeConstants.RAS_MaxEntryName + 1)]
public string szEntryName;
//#if WINVER5
// public int dwFlags;
// [MarshalAs(UnmanagedType.ByValTStr,SizeConst=260+1)]
// public string szPhonebookPath;
//#endif
}
public class RAS

{

[DllImport(
"Rasapi32.dll", EntryPoint =
"RasEnumConnectionsA",

SetLastError =
true)]
internal static extern int RasEnumConnections

(
ref RASCONN lprasconn,
// buffer to receive connections data
ref int lpcb,
// size in bytes of buffer
ref int lpcConnections
// number of connections written to buffer
);


[DllImport(
"rasapi32.dll", CharSet = CharSet.Auto)]
internal static extern uint RasGetConnectionStatistics(

IntPtr hRasConn,
// handle to the connection
[In, Out]RasStats lpStatistics
// buffer to receive statistics
);

[DllImport(
"rasapi32.dll", CharSet = CharSet.Auto)]
public extern static uint RasHangUp(

IntPtr hrasconn
// handle to the RAS connection to hang up
);

[DllImport(
"rasapi32.dll", CharSet = CharSet.Auto)]
public extern static uint RasEnumEntries(
string reserved,
// reserved, must be NULL
string lpszPhonebook,
// pointer to full path and
// file name of phone-book file
[In, Out]RasEntryName[] lprasentryname,
// buffer to receive
// phone-book entries
ref int lpcb,
// size in bytes of buffer
out int lpcEntries
// number of entries written
// to buffer
);

[DllImport(
"wininet.dll", CharSet = CharSet.Auto)]
public extern static int InternetDial(

IntPtr hwnd,

[In]
string lpszConnectoid,
uint dwFlags,
ref int lpdwConnection,
uint dwReserved

);
public RAS()

{

}

}
public enum DEL_CACHE_TYPE
//要删除的类型。
{

File,
//表示internet临时文件
Cookie
//表示Cookie
}
public class RASDisplay

{

[DllImport(
"wininet.dll", CharSet = CharSet.Auto)]
public static extern bool DeleteUrlCacheEntry(

DEL_CACHE_TYPE type

);
private string m_duration;
private string m_ConnectionName;
private string[] m_ConnectionNames;
private double m_TX;
private double m_RX;
private bool m_connected;
private IntPtr m_ConnectedRasHandle;

RasStats status =
new RasStats();
public RASDisplay()

{

m_connected =
true;

RAS lpras =
new RAS();

RASCONN lprasConn =
new RASCONN();

lprasConn.dwSize = Marshal.SizeOf(
typeof(RASCONN));

lprasConn.hrasconn = IntPtr.Zero;
int lpcb = 0;
int lpcConnections = 0;
int nRet = 0;

lpcb = Marshal.SizeOf(
typeof(RASCONN));

nRet = RAS.RasEnumConnections(
ref lprasConn,
ref lpcb,
ref
lpcConnections);
if (nRet != 0)

{

m_connected =
false;
return;

}
if (lpcConnections > 0)

{
//for (int i = 0; i < lpcConnections; i++)
//{
RasStats stats =
new RasStats();

m_ConnectedRasHandle = lprasConn.hrasconn;

RAS.RasGetConnectionStatistics(lprasConn.hrasconn, stats);


m_ConnectionName = lprasConn.szEntryName;
int Hours = 0;
int Minutes = 0;
int Seconds = 0;

Hours = ((stats.dwConnectionDuration / 1000) / 3600);

Minutes = ((stats.dwConnectionDuration / 1000) / 60) - (Hours * 60);

Seconds = ((stats.dwConnectionDuration / 1000)) - (Minutes * 60) - (Hours * 3600);


m_duration = Hours +
" hours " + Minutes +
" minutes " + Seconds +
" secs";

m_TX = stats.dwBytesXmited;

m_RX = stats.dwBytesRcved;
//}
}
else
{

m_connected =
false;

}

int lpNames = 1;
int entryNameSize = 0;
int lpSize = 0;

RasEntryName[] names =
null;

entryNameSize = Marshal.SizeOf(
typeof(RasEntryName));

lpSize = lpNames * entryNameSize;

names =
new RasEntryName[lpNames];

names[0].dwSize = entryNameSize;
uint retval = RAS.RasEnumEntries(
null,
null, names,
ref lpSize,
out lpNames);
//if we have more than one connection, we need to do it again
if (lpNames > 1)

{

names =
new RasEntryName[lpNames];
for (
int i = 0; i < names.Length; i++)

{

names[i].dwSize = entryNameSize;

}

retval = RAS.RasEnumEntries(
null,
null, names,
ref lpSize,
out lpNames);

}

m_ConnectionNames =
new string[names.Length];

if (lpNames > 0)

{
for (
int i = 0; i < names.Length; i++)

{

m_ConnectionNames[i] = names[i].szEntryName;

}

}

}
public string Duration

{

get

{
return m_connected ? m_duration : "";

}

}
public string[] Connections

{

get

{
return m_ConnectionNames;

}

}
public double BytesTransmitted

{

get

{
return m_connected ? m_TX : 0;

}

}
public double BytesReceived

{

get

{
return m_connected ? m_RX : 0;

}

}
public string ConnectionName

{

get

{
return m_connected ? m_ConnectionName : "";

}

}
public bool IsConnected

{

get

{
return m_connected;

}

}
public int Connect(
string Connection)

{
int temp = 0;
uint INTERNET_AUTO_DIAL_UNATTENDED = 2;
int retVal = RAS.InternetDial(IntPtr.Zero, Connection, INTERNET_AUTO_DIAL_UNATTENDED,
ref temp, 0);
return retVal;

}
public void Disconnect()

{

RAS.RasHangUp(m_ConnectedRasHandle);

}

}