delphi - 使用 Delphi 检测互联网连接激活

Question

我使用 3G 无线卡已经有一段时间了，每次连接时，我的防病毒软件都会启动更新。

我想知道我可以使用哪些 Win32 API 函数集来获取通知或查询即将出现的 Internet 连接事件？

Delphi 是否已经有一组移植的 header ？

Answer 1

我参与了一个项目，每当用户通过 VPN 连接我们的网络时，就会运行用户的登录脚本。为此，我编写了一个辅助单元，用于检索适配器信息并将其存储到一个简单的记录中。

然后我设置了一个注册表通知，see here for how to do that in Delphi

注册表通知位于HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces。每当 Windows 获取新的 IP 地址或对适配器连接信息进行任何类型的更改时，都会触发此通知事件。当此事件触发时，我调用该函数(在下面的代码中)来检索有关适配器的更新信息。我将这些新信息与之前记录的信息进行了比较...这意味着我必须保存之前的适配器信息查询才能知道是否发生了更改。

无论如何，这是我的辅助单元:

unit uAdapterInfo;

interface

uses
  Classes,
  SysUtils;

const
  MAX_INTERFACE_NAME_LEN = $100;
  ERROR_SUCCESS   = 0;
  MAXLEN_IFDESCR  = $100;
  MAXLEN_PHYSADDR = 8;

  MIB_IF_OPER_STATUS_NON_OPERATIONAL = 0;
  MIB_IF_OPER_STATUS_UNREACHABLE = 1;
  MIB_IF_OPER_STATUS_DISCONNECTED = 2;
  MIB_IF_OPER_STATUS_CONNECTING  = 3;
  MIB_IF_OPER_STATUS_CONNECTED   = 4;
  MIB_IF_OPER_STATUS_OPERATIONAL = 5;

  MIB_IF_TYPE_OTHER    = 1;
  MIB_IF_TYPE_ETHERNET = 6;
  MIB_IF_TYPE_TOKENRING = 9;
  MIB_IF_TYPE_FDDI     = 15;
  MIB_IF_TYPE_PPP      = 23;
  MIB_IF_TYPE_LOOPBACK = 24;
  MIB_IF_TYPE_SLIP     = 28;

  MIB_IF_ADMIN_STATUS_UP      = 1;
  MIB_IF_ADMIN_STATUS_DOWN    = 2;
  MIB_IF_ADMIN_STATUS_TESTING = 3;

  _MAX_ROWS_ = 20;
  ANY_SIZE   = 1;


type
  MIB_IFROW = record
    wszName:    array[0 .. (MAX_INTERFACE_NAME_LEN * 2 - 1)] of ansichar;
    dwIndex:    longint;
    dwType:     longint;
    dwMtu:      longint;
    dwSpeed:    longint;
    dwPhysAddrLen: longint;
    bPhysAddr:  array[0 .. (MAXLEN_PHYSADDR - 1)] of byte;
    dwAdminStatus: longint;
    dwOperStatus: longint;
    dwLastChange: longint;
    dwInOctets: longint;
    dwInUcastPkts: longint;
    dwInNUcastPkts: longint;
    dwInDiscards: longint;
    dwInErrors: longint;
    dwInUnknownProtos: longint;
    dwOutOctets: longint;
    dwOutUcastPkts: longint;
    dwOutNUcastPkts: longint;
    dwOutDiscards: longint;
    dwOutErrors: longint;
    dwOutQLen:  longint;
    dwDescrLen: longint;
    bDescr:     array[0 .. (MAXLEN_IFDESCR - 1)] of ansichar;
  end;

type
  MIB_IPADDRROW = record
    dwAddr:      longint;
    dwIndex:     longint;
    dwMask:      longint;
    dwBCastAddr: longint;
    dwReasmSize: longint;
    unused1:     word;
    unused2:     word;
  end;

type
  _IfTable = record
    nRows: longint;
    ifRow: array[1.._MAX_ROWS_] of MIB_IFROW;
  end;

type
  _IpAddrTable = record
    dwNumEntries: longint;
    table: array[1..ANY_SIZE] of MIB_IPADDRROW;
  end;



function GetIfTable(pIfTable: Pointer; var pdwSize: longint; bOrder: longint): longint;
  stdcall;
function GetIpAddrTable(pIpAddrTable: Pointer; var pdwSize: longint;
  bOrder: longint): longint; stdcall;

function Get_if_type(iType: integer): string;
function Get_if_admin_status(iStatus: integer): string;
function Get_if_oper_status(iStatus: integer): string;


implementation

function GetIfTable; stdcall; external 'IPHLPAPI.DLL';
function GetIpAddrTable; stdcall; external 'IPHLPAPI.DLL';

function Get_if_type(iType: integer): string;
var
  sResult: string;
begin
  sResult := 'UNKNOWN';
  case iType of
    1: sResult   := 'Other';
    6: sResult   := 'Ethernet';
    9: sResult   := 'Tokenring';
    15: sResult  := 'FDDI';
    23: sResult  := 'PPP';
    24: sResult  := 'Local loopback';
    28: sResult  := 'SLIP';
    37: sResult  := 'ATM';
    71: sResult  := 'IEEE 802.11';
    131: sResult := 'Tunnel';
    144: sResult := 'IEEE 1394 (Firewire)';
  end;

  Result := sResult;
end;

function Get_if_admin_status(iStatus: integer): string;
var
  sResult: string;
begin
  sResult := 'UNKNOWN';

  case iStatus of
    1: sResult := 'UP';
    2: sResult := 'DOWN';
    3: sResult := 'TESTING';
  end;

  Result := sResult;
end;

function Get_if_oper_status(iStatus: integer): string;
var
  sResult: string;
begin
  sResult := 'UNKNOWN';

  case iStatus of
    0: sResult := 'NON_OPERATIONAL';
    1: sResult := 'UNREACHABLE';
    2: sResult := 'DISCONNECTED';
    3: sResult := 'CONNECTING';
    4: sResult := 'CONNECTED';
    5: sResult := 'OPERATIONAL';
  end;

  Result := sResult;
end;

end.

为了从另一个单元使用此单元，我创建了以下函数，该函数填充了一个名为 TAdapterInfo 的自定义类型(在我的主单元中声明):

type
  TAdapterInfo = array of record
    dwIndex:    longint;
    dwType:     longint;
    dwMtu:      longint;
    dwSpeed:    extended;
    dwPhysAddrLen: longint;
    bPhysAddr:  string;
    dwAdminStatus: longint;
    dwOperStatus: longint;
    dwLastChange: longint;
    dwInOctets: longint;
    dwInUcastPkts: longint;
    dwInNUcastPkts: longint;
    dwInDiscards: longint;
    dwInErrors: longint;
    dwInUnknownProtos: longint;
    dwOutOctets: longint;
    dwOutUcastPkts: longint;
    dwOutNUcastPkts: longint;
    dwOutDiscards: longint;
    dwOutErrors: longint;
    dwOutQLen:  longint;
    dwDescrLen: longint;
    bDescr:     string;
    sIpAddress: string;
    sIpMask:    string;
  end;

//////////

function Get_EthernetAdapterDetail(var AdapterDataFound: TAdapterInfo): boolean;
var
  pIfTable: ^_IfTable;
  pIpTable: ^_IpAddrTable;
  ifTableSize, ipTableSize: longint;
  tmp:      string;
  i, j, k, m: integer;
  ErrCode:  longint;
  sAddr, sMask: in_addr;
  IPAddresses, IPMasks: TStringList;
  sIPAddressLine, sIPMaskLine: string;
  bResult:  boolean;
begin
  bResult  := True; //default return value
  pIfTable := nil;
  pIpTable := nil;

  IPAddresses := TStringList.Create;
  IPMasks     := TStringList.Create;

  try
    // First: just get the buffer size.
    // TableSize returns the size needed.
    ifTableSize := 0; // Set to zero so the GetIfTabel function
    // won't try to fill the buffer yet,
    // but only return the actual size it needs.
    GetIfTable(pIfTable, ifTableSize, 1);
    if (ifTableSize < SizeOf(MIB_IFROW) + Sizeof(longint)) then
    begin
      bResult := False;
      Result  := bResult;
      Exit; // less than 1 table entry?!
    end;

    ipTableSize := 0;
    GetIpAddrTable(pIpTable, ipTableSize, 1);
    if (ipTableSize < SizeOf(MIB_IPADDRROW) + Sizeof(longint)) then
    begin
      bResult := False;
      Result  := bResult;
      Exit; // less than 1 table entry?!
    end;

    // Second:
    // allocate memory for the buffer and retrieve the
    // entire table.
    GetMem(pIfTable, ifTableSize);
    ErrCode := GetIfTable(pIfTable, ifTableSize, 1);

    if ErrCode <> ERROR_SUCCESS then
    begin
      bResult := False;
      Result  := bResult;
      Exit; // OK, that did not work. 
      // Not enough memory i guess.
    end;

    GetMem(pIpTable, ipTableSize);
    ErrCode := GetIpAddrTable(pIpTable, ipTableSize, 1);

    if ErrCode <> ERROR_SUCCESS then
    begin
      bResult := False;
      Result  := bResult;
      Exit;
    end;

    for k := 1 to pIpTable^.dwNumEntries do
    begin
      sAddr.S_addr := pIpTable^.table[k].dwAddr;
      sMask.S_addr := pIpTable^.table[k].dwMask;

      sIPAddressLine := Format('0x%8.8x', [(pIpTable^.table[k].dwIndex)]) +
        '=' + Format('%s', [inet_ntoa(sAddr)]);
      sIPMaskLine    := Format('0x%8.8x', [(pIpTable^.table[k].dwIndex)]) +
        '=' + Format('%s', [inet_ntoa(sMask)]);

      IPAddresses.Add(sIPAddressLine);
      IPMasks.Add(sIPMaskLine);
    end;

    SetLength(AdapterDataFound, pIfTable^.nRows); //initialize the array or records
    for i := 1 to pIfTable^.nRows do
      try
        //if pIfTable^.ifRow[i].dwType=MIB_IF_TYPE_ETHERNET then
        //begin
        m := i - 1;
        AdapterDataFound[m].dwIndex := 4;//(pIfTable^.ifRow[i].dwIndex);
        AdapterDataFound[m].dwType := (pIfTable^.ifRow[i].dwType);
        AdapterDataFound[m].dwIndex := (pIfTable^.ifRow[i].dwIndex);
        AdapterDataFound[m].sIpAddress :=
          IPAddresses.Values[Format('0x%8.8x', [(pIfTable^.ifRow[i].dwIndex)])];
        AdapterDataFound[m].sIpMask :=
          IPMasks.Values[Format('0x%8.8x', [(pIfTable^.ifRow[i].dwIndex)])];
        AdapterDataFound[m].dwMtu := (pIfTable^.ifRow[i].dwMtu);
        AdapterDataFound[m].dwSpeed := (pIfTable^.ifRow[i].dwSpeed);
        AdapterDataFound[m].dwAdminStatus := (pIfTable^.ifRow[i].dwAdminStatus);
        AdapterDataFound[m].dwOperStatus := (pIfTable^.ifRow[i].dwOperStatus);
        AdapterDataFound[m].dwInUcastPkts := (pIfTable^.ifRow[i].dwInUcastPkts);
        AdapterDataFound[m].dwInNUcastPkts := (pIfTable^.ifRow[i].dwInNUcastPkts);
        AdapterDataFound[m].dwInDiscards := (pIfTable^.ifRow[i].dwInDiscards);
        AdapterDataFound[m].dwInErrors := (pIfTable^.ifRow[i].dwInErrors);
        AdapterDataFound[m].dwInUnknownProtos := (pIfTable^.ifRow[i].dwInUnknownProtos);
        AdapterDataFound[m].dwOutNUcastPkts := (pIfTable^.ifRow[i].dwOutNUcastPkts);
        AdapterDataFound[m].dwOutUcastPkts := (pIfTable^.ifRow[i].dwOutUcastPkts);
        AdapterDataFound[m].dwOutDiscards := (pIfTable^.ifRow[i].dwOutDiscards);
        AdapterDataFound[m].dwOutErrors := (pIfTable^.ifRow[i].dwOutErrors);
        AdapterDataFound[m].dwOutQLen := (pIfTable^.ifRow[i].dwOutQLen);
        AdapterDataFound[m].bDescr := (pIfTable^.ifRow[i].bDescr);

        tmp := '';
        for j := 0 to pIfTable^.ifRow[i].dwPhysAddrLen - 1 do
        begin
          if Length(tmp) > 0 then
            tmp := tmp + '-' + format('%.2x', [pIfTable^.ifRow[i].bPhysAddr[j]])
          else
            tmp := tmp + format('%.2x', [pIfTable^.ifRow[i].bPhysAddr[j]]);
        end;

        if Length(tmp) > 0 then
        begin
          AdapterDataFound[m].bPhysAddr := tmp;
        end;
      except
        bResult := False;
        Result  := bResult;
        Exit;
      end;
  finally
    if Assigned(pIfTable) then
    begin
      FreeMem(pIfTable, ifTableSize);
    end;

    FreeAndNil(IPMasks);
    FreeAndNil(IPAddresses);
  end;

  Result := bResult;
end;

顺便说一句，我还使用了这个单元和几乎完全相同的代码来创建 ifconfig -a 的副本，其中 can be found on github 。我这样做主要是为了自学如何完成这项任务。