Wie kann man erkennen ob, eine der Netzerkkarten des Systems mit einem Netzwerk verbunden ist

Kann mit denn keiner helfen
Es musst doch irgendwie möglich sein zu erkennen, ob in einer der Netzwerkkarten ein Netwerkkabel steckt, oder ob in keiner eins ist.

Nein, geht nicht: http://www.marian-aldenhoevel.de/dojo/internet.html

Zitat von Delphi Star:

... ob in einer der Netzwerkkarten ein Netwerkkabel steckt, ....

Hmmm... Seit WIN 2000 wird einem dies ja vom OS angezeigt. Jetzt muss man nur rausfinden ob es auch eine API-Funktion gibt um den Status der Netzwerkberbindung in erfahrung zu bringen.

Hi,

folgende Sourcen sind nicht von mir, weiss auch nicht mehr woher ich sie habe und getstet sind erst recht nicht, aber vielleicht helfen sie trotzdem.

zusammenfalten · markieren

Delphi-Quellcode:

function IsNetworkConnected: Boolean;
begin
  if GetSystemMetrics(SM_NETWORK) and $01 = $01 then
  begin
    Result := True;
  end
  else
  begin
    Result := False;
  end;
end;

zusammenfalten · markieren

Delphi-Quellcode:

unit NetworkFunctions;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, WinInet, WinSock;

type
  PNetResourceArray = ^TNetResourceArray;
  TNetResourceArray = array[0..100] of TNetResource;

type
  IPAddr = DWORD;

  PICMP_ECHO_REPLY = ^ICMP_ECHO_REPLY;
  ICMP_ECHO_REPLY = packed record
    Address : ULONG;
    Status : ULONG;
    RoundTripTime : ULONG;
    DataSize : WORD;
    Reserved : WORD;
    Data : Pointer;
  end;

  PIP_OPTION_INFORMATION = ^IP_OPTION_INFORMATION;
  IP_OPTION_INFORMATION = packed record
    Ttl : byte;
    Tos : byte;
    Flags : byte;
    OptionsSize : byte;
    OptionsData : Pointer;
  end;

procedure GetComputerList(List: TStrings);
function InternetAvailable:Boolean; // Only DFÜ / RAS
function Ping(IP:string; TimeOut:Cardinal) : Boolean; // TimeOut ~1000
function GetNetworkName(IPAddr: string): string;
function GetIp(const HostName: string): string;

implementation

function IcmpCreateFile : DWORD; stdcall; external 'icmp.dll';
function IcmpCloseHandle(const IcmpHandle : DWORD) : longbool; stdcall; external 'icmp.dll';
function IcmpSendEcho(const IcmpHandle : DWORD;const DestinationAddress : IPAddr;const RequestData : Pointer;const RequestSize : WORD;const RequestOptions : PIP_OPTION_INFORMATION;const ReplyBuffer : Pointer;const ReplySize : DWORD;const TimeOut : DWORD) : DWORD; stdcall; external 'icmp.dll' 

function GetNetworkName(IPAddr: string): string;
  var SockAddrIn: TSockAddrIn;
      HostEnt: PHostEnt;
      WSAData: TWSAData;
begin
  WSAStartup($101, WSAData);
  SockAddrIn.sin_addr.s_addr := inet_addr(PChar(IPAddr));
  HostEnt:= GetHostByAddr(@SockAddrIn.sin_addr.S_addr, 4, AF_INET);
  if HostEnt <> nil then
    Result := StrPas(Hostent^.h_name)
  else
    Result := '';
end;

function GetIp(const HostName: string): string;
  type
    TaPInAddr = array[0..10] of PInAddr;
    PaPInAddr = ^TaPInAddr;
  var
    phe: PHostEnt;
    pptr: PaPInAddr;
    i: Integer;
    GInitData: TWSAData;
begin
  WSAStartup($101, GInitData);
  Result := '';
  phe := GetHostByName(PChar(HostName));
  if phe = nil then Exit;
  pPtr := PaPInAddr(phe^.h_addr_list);
  i := 0;
  while pPtr^[i] <> nil do begin
    Result := inet_ntoa(pptr^[i]^);
    Inc(i);
  end;
  WSACleanup;

end;

function Ping(IP:string; TimeOut:Cardinal):Boolean;
  var hICMP : DWORD;
      pierWork : PICMP_ECHO_REPLY;
      dwSize : DWORD;
      Class1,Class2,Class3,Class4 : String;
      i,j : Byte;
begin
  Result:=False;
  j:=1;
  for i:=1 to Length(IP) do begin
    if IP[i]<>'.' then begin
      case j of
        1: Class1:=Class1+IP[i];
        2: Class2:=Class2+IP[i];
        3: Class3:=Class3+IP[i];
        4: Class4:=Class4+IP[i];
      end;
    end else
      Inc(j);
  end;
  hICMP := IcmpCreateFile;
  if hICMP = INVALID_HANDLE_VALUE then exit;
  try
    dwSize := SizeOf(ICMP_ECHO_REPLY)+8;
    pierWork := AllocMem(dwSize);
    try
      if IcmpSendEcho(hICMP,MAKELONG(MAKEWORD(StrToInt(Class1), StrToInt(Class2)),MAKEWORD(StrToInt(Class3), StrToInt(Class4))),nil,0,nil,pierWork,dwSize,TimeOut) = 0 then
        Result:=False
      else
        Result:=True;
    finally
      FreeMem(pierWork,dwSize);
    end;
  finally
    IcmpCloseHandle(hIcmp);
  end;
end;

  // Nur für DFÜ / RAS
function InternetAvailable:Boolean;
begin
  Result := InternetCheckConnection(nil, 0, 0);
end;

function CreateNetResourceList(ResourceType: DWord;
                              NetResource: PNetResource;
                              out Entries: DWord;
                              out List: PNetResourceArray): Boolean;
var
  EnumHandle: THandle;
  BufSize: DWord;
  Res: DWord;
begin
  Result := False;
  List := Nil;
  Entries := 0;
  if WNetOpenEnum(RESOURCE_GLOBALNET,ResourceType,0,NetResource,EnumHandle) = NO_ERROR then begin
    try
      BufSize := $4000; // 16 kByte
      GetMem(List, BufSize);
      try
        repeat
          Entries := DWord(-1);
          FillChar(List^, BufSize, 0);
          Res := WNetEnumResource(EnumHandle, Entries, List, BufSize);
          if Res = ERROR_MORE_DATA then begin
            ReAllocMem(List, BufSize);
          end;
        until Res <> ERROR_MORE_DATA;

        Result := Res = NO_ERROR;
        if not Result then begin
          FreeMem(List);
          List := Nil;
          Entries := 0;
        end;
      except
        FreeMem(List);
        raise;
      end;
    finally
      WNetCloseEnum(EnumHandle);
    end;
  end;
end;

procedure GetComputerList(List: TStrings);
  procedure ScanLevel(ResourceType, DisplayType: DWord; NetResource: PNetResource);
  var
    Entries: DWord;
    NetResourceList: PNetResourceArray;
    i: Integer;
  begin
    if CreateNetResourceList(ResourceType, NetResource, Entries, NetResourceList) then try
      for i := 0 to Integer(Entries) - 1 do begin
        if (DisplayType = RESOURCEDISPLAYTYPE_GENERIC) or
          (NetResourceList[i].dwDisplayType = DisplayType) then begin
          List.AddObject(NetResourceList[i].lpRemoteName,
                        Pointer(NetResourceList[i].dwDisplayType));
        end;
        if (NetResourceList[i].dwUsage and RESOURCEUSAGE_CONTAINER) <> 0 then
          ScanLevel(RESOURCETYPE_DISK, RESOURCEDISPLAYTYPE_SERVER,@NetResourceList[i]);
      end;
    finally
      FreeMem(NetResourceList);
    end;
  end;
begin
  ScanLevel(RESOURCETYPE_DISK, RESOURCEDISPLAYTYPE_SERVER, Nil);
end;

end.