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如何得知網路連接正常?

答題得分者是:ddy
junlin
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#1 引用回覆 回覆 發表時間:2002-08-21 17:49:56 IP:61.218.xxx.xxx 未訂閱
在LAN中,如何得知A可正常連至B? 就是在檔案總管中輸入\\B,可以看到B
turboted
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#2 引用回覆 回覆 發表時間:2002-08-21 20:08:19 IP:210.71.xxx.xxx 未訂閱
通常就算是LAN也會有IP..你可以使用PING的方法得知是否還在連線狀態 Send a packet
領航天使
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#3 引用回覆 回覆 發表時間:2002-08-21 20:30:10 IP:192.168.xxx.xxx 未訂閱
引言: 通常就算是LAN也會有IP..你可以使用PING的方法得知是否還在連線狀態 Send a packet
若只採用NETBEUI的通訊協定雖可看到對方電腦名稱確可以無IP, 所以我猜想可以用廣播的方式試看看! ~~~Delphi K.Top討論區站長~~~
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~~~Delphi K.Top討論區站長~~~
ddy
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#4 引用回覆 回覆 發表時間:2002-08-21 23:25:57 IP:61.59.xxx.xxx 未訂閱
junlin 兄    這個問題問得有點玄呀…:p \\b 不能連就代表不正常呀…,可以就知道可以連呀,不是這樣嗎?    提供一段由程式可取得網路上的芳鄰,可藉此判斷某電腦是否存在
//在程式中動態取得Win95/98網路鄰居中工作組及電腦名
//可參考下面代碼,或許有所幫助:    procedure GetDomainList(TV:TTreeView);
var
a : Integer;
ErrCode : Integer;
NetRes : Array[0..1023] of TNetResource;
EnumHandle : THandle;
EnumEntries : DWord;
BufferSize : DWord;
s : string;
itm : TTreeNode;
begin
{ Start here }
try
  with NetRes[0] do begin
    dwScope := RESOURCE_GLOBALNET;
    dwType := RESOURCETYPE_ANY;
    dwDisplayType := RESOURCEDISPLAYTYPE_DOMAIN;
    dwUsage := RESOURCEUSAGE_CONTAINER;
    lpLocalName := nil;
    lpRemoteName := nil;
    lpComment := nil;
    lpProvider := nil;
  end;
{ get net root }
  ErrCode := WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_ANY,
    RESOURCEUSAGE_CONTAINER, @NetRes[0], EnumHandle);
  if ErrCode = NO_ERROR then
  begin
    EnumEntries := 1;
    BufferSize := SizeOf(NetRes);
    ErrCode := WNetEnumResource(EnumHandle, EnumEntries, @NetRes[0], BufferSize);
    WNetCloseEnum(EnumHandle);
    ErrCode := WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_ANY,
      RESOURCEUSAGE_CONTAINER, @NetRes[0], EnumHandle);
    EnumEntries := 1024;
    BufferSize := SizeOf(NetRes);
    ErrCode := WNetEnumResource(EnumHandle, EnumEntries, @NetRes[0], BufferSize);
    if ErrCode = No_Error then with TV do try
        a := 0;
        Items.BeginUpDate;
        Items.Clear;
        Itm := Items.Add(TV.Selected, string(NetRes[0].lpProvider));
        Itm.ImageIndex := 0;
        Itm.SelectedIndex := 0;    { get domains }    //        下面的一個單元定義了一個元件.TNetworkBrowser, 可以枚舉hierachical樹上所有的網路資源.實際上瀏覽是要花費很長時間的, 這您可以通過在WINDOWS資源管理器中打開"整個網路" 來比較一下.如果你設置SCOPE屬性 ?nsContext, 你就可以看到和網路鄰居中一樣的機器列表.    unit NetBrwsr;    interface    uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs;    type
  TNetScope = (nsConnected, nsGlobal, nsRemembered, nsContext);
  TNetResourceType = (nrAny, nrDisk, nrPrint);
  TNetDisplay = (ndDomain, ndGeneric, ndServer, ndShare, ndFile, ndGroup,
    ndNetwork, ndRoot, ndShareAdmin, ndDirectory, ndTree, ndNDSContainer);
  TNetUsage = set of (nuConnectable, nuContainer);      TNetworkItems = class;      TNetworkItem = class
  private
    FScope: TNetScope;
    FResourceType: TNetResourceType;
    FDisplay: TNetDisplay;
    FUsage: TNetUsage;
    FLocalName: string;
    FRemoteName: string;
    FComment: string;
    FProvider: string;
    FSubItems: TNetworkItems;
  public
    constructor Create;
    destructor Destroy; override;
    property Scope: TNetScope read FScope;
    property ResourceType: TNetResourceType read FResourceType;
    property Display: TNetDisplay read FDisplay;
    property Usage: TNetUsage read FUsage;
    property LocalName: string read FLocalName;
    property RemoteName: string read FRemoteName;
    property Comment: string read FComment;
    property Provider: string read FProvider;
    property SubItems: TNetworkItems read FSubItems;
  end;      TNetworkItems = class
  private
    FList: TList;
    procedure SetItem(Index: Integer; Value: TNetworkItem);
    function GetItem(Index: Integer): TNetworkItem;
    function GetCount: Integer;
  public
    constructor Create;
    destructor Destroy; override;
    procedure Clear;
    procedure Add(Item: TNetworkItem);
    procedure Delete(Index: Integer);
    property Items[Index: Integer]: TNetworkItem read GetItem write
    SetItem; default;
    property Count: Integer read GetCount;
  end;      TNetworkBrowser = class(TComponent)
  private
    FItems: TNetworkItems;
    FScope: TNetScope;
    FResourceType: TNetResourceType;
    FUsage: TNetUsage;
    FActive: Boolean;
    procedure Refresh;
    procedure SetActive(Value: Boolean);
    procedure SetScope(Value: TNetScope);
    procedure SetResourceType(Value: TNetResourceType);
    procedure SetUsage(Value: TNetUsage);
    procedure EnumerateNet(NetItems: TNetworkItems; lpnr: PNetResource);
  protected
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
    procedure Open;
    procedure Close;
    property Items: TNetworkItems read FItems;
  published
    property Scope: TNetScope read FScope write SetScope default nsGlobal;
    property ResourceType: TNetResourceType read FResourceType
      write SetResourceType default nrAny;
    property Usage: TNetUsage read FUsage write SetUsage default [];
    property Active: Boolean read FActive write SetActive default False;
  end;    implementation    type
  PNetResourceArray = ^TNetResourceArray;
  TNetResourceArray = array[0..0] of TNetResource;    { TNetworkItem }    constructor TNetworkItem.Create;
begin
  inherited;
  FSubItems := TNetworkItems.Create;
end;    destructor TNetworkItem.Destroy;
begin
  if FSubItems <> nil then
    FSubItems.Free;
  inherited;
end;    { TNetworkItems }    constructor TNetworkItems.Create;
begin
  inherited;
  FList := TList.Create;
end;    destructor TNetworkItems.Destroy;
begin
  Clear;
  if FList <> nil then
    FList.Free;
  inherited;
end;    procedure TNetworkItems.SetItem(Index: Integer; Value: TNetworkItem);
begin
  if (FList.Items[Index] <> nil) and (FList.Items[Index] <> Value) then
    TNetworkItem(FList.Items[Index]).Free;
  FList.Items[Index] := Value;
end;    function TNetworkItems.GetItem(Index: Integer): TNetworkItem;
begin
  Result := TNetworkItem(FList.Items[Index]);
end;    procedure TNetworkItems.Clear;
begin
  while Count > 0 do
    Delete(0);
end;    procedure TNetworkItems.Add(Item: TNetworkItem);
begin
  FList.Add(Item);
end;    procedure TNetworkItems.Delete(Index: Integer);
begin
  if FList.Items[Index] <> nil then
    TNetworkItem(FList.Items[Index]).Free;
  FList.Delete(Index);
end;    function TNetworkItems.GetCount: Integer;
begin
  if FList <> nil then
    Result := FList.Count
  else
    Result := 0;
end;    { TNetworkBrowser }    constructor TNetworkBrowser.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  FItems := TNetworkItems.Create;
  FScope := nsGlobal;
  FResourceType := nrAny;
  FUsage := [];
end;    destructor TNetworkBrowser.Destroy;
begin
  if FItems <> nil then
    FItems.Free;
  inherited;
end;    procedure TNetworkBrowser.EnumerateNet(NetItems: TNetworkItems; lpnr:
  PNetResource);
var
  dwResult, dwResultEnum: Integer;
  hEnum: THandle;
  cbBuffer, cEntries, i: Integer;
  nrArray: PNetResourceArray;
  NewItem: TNetworkItem;
  dwScope, dwType, dwUsage: Integer;
begin
  cbBuffer := 16384;
  cEntries := $FFFFFFFF;      case FScope of
    nsConnected: dwScope := RESOURCE_CONNECTED;
    nsGlobal: dwScope := RESOURCE_GLOBALNET;
    nsRemembered: dwScope := RESOURCE_REMEMBERED;
    nsContext: dwScope := RESOURCE_CONTEXT;
  else
    dwScope := RESOURCE_GLOBALNET;
  end;
  case FResourceType of
    nrAny: dwType := RESOURCETYPE_ANY;
    nrDisk: dwType := RESOURCETYPE_DISK;
    nrPrint: dwType := RESOURCETYPE_PRINT;
  else
    dwType := RESOURCETYPE_ANY;
  end;
  dwUsage := 0;
  if nuConnectable in FUsage then
    dwUsage := dwUsage or RESOURCEUSAGE_CONNECTABLE;
  if nuContainer in FUsage then
    dwUsage := dwUsage or RESOURCEUSAGE_CONTAINER;      dwResult := WNetOpenEnum(dwScope, dwType, dwUsage, lpnr, hEnum);
  if dwResult <> NO_ERROR then Exit;      GetMem(nrArray, cbBuffer);
  repeat
    dwResultEnum := WNetEnumResource(hEnum, cEntries, nrArray, cbBuffer);
    if dwResultEnum = NO_ERROR then
      for i := 0 to cEntries - 1 do
      begin
        NewItem := TNetworkItem.Create;
        case nrArray[i].dwScope of
          RESOURCE_CONNECTED: NewItem.FScope := nsConnected;
          RESOURCE_GLOBALNET: NewItem.FScope := nsGlobal;
          RESOURCE_REMEMBERED: NewItem.FScope := nsRemembered;
          RESOURCE_CONTEXT: NewItem.FScope := nsContext;
        else
          NewItem.FScope := nsGlobal;
        end;
        case nrArray[i].dwType of
          RESOURCETYPE_ANY: NewItem.FResourceType := nrAny;
          RESOURCETYPE_DISK: NewItem.FResourceType := nrDisk;
          RESOURCETYPE_PRINT: NewItem.FResourceType := nrPrint;
        else
          NewItem.FResourceType := nrAny;
        end;
        case nrArray[i].dwDisplayType of
          RESOURCEDISPLAYTYPE_GENERIC: NewItem.FDisplay := ndGeneric;
          RESOURCEDISPLAYTYPE_DOMAIN: NewItem.FDisplay := ndDomain;
          RESOURCEDISPLAYTYPE_SERVER: NewItem.FDisplay := ndServer;
          RESOURCEDISPLAYTYPE_SHARE: NewItem.FDisplay := ndShare;
          RESOURCEDISPLAYTYPE_FILE: NewItem.FDisplay := ndFile;
          RESOURCEDISPLAYTYPE_GROUP: NewItem.FDisplay := ndGroup;
          RESOURCEDISPLAYTYPE_NETWORK: NewItem.FDisplay := ndNetwork;
          RESOURCEDISPLAYTYPE_ROOT: NewItem.FDisplay := ndRoot;
          RESOURCEDISPLAYTYPE_SHAREADMIN: NewItem.FDisplay :=
            ndShareAdmin;
          RESOURCEDISPLAYTYPE_DIRECTORY: NewItem.FDisplay :=
            ndDirectory;
          RESOURCEDISPLAYTYPE_TREE: NewItem.FDisplay := ndTree;
          RESOURCEDISPLAYTYPE_NDSCONTAINER: NewItem.FDisplay :=
            ndNDSContainer;
        else
          NewItem.FDisplay := ndGeneric;
        end;
        NewItem.FUsage := [];
        if nrArray[i].dwUsage and RESOURCEUSAGE_CONNECTABLE <> 0 then
          Include(NewItem.FUsage, nuConnectable);
        if nrArray[i].dwUsage and RESOURCEUSAGE_CONTAINER <> 0 then
          Include(NewItem.FUsage, nuContainer);
        NewItem.FLocalName := StrPas(nrArray[i].lpLocalName);
        NewItem.FRemoteName := StrPas(nrArray[i].lpRemoteName);
        NewItem.FComment := StrPas(nrArray[i].lpComment);
        NewItem.FProvider := StrPas(nrArray[i].lpProvider);
        NetItems.Add(NewItem);
// if container, call recursively
        if (nuContainer in NewItem.FUsage) and (FScope <> nsContext) then
          EnumerateNet(NewItem.FSubItems, @nrArray[i])
      end;
  until dwResultEnum = ERROR_NO_MORE_ITEMS;      FreeMem(nrArray);
  WNetCloseEnum(hEnum);
end;    procedure TNetworkBrowser.Refresh;
begin
  FItems.Clear;
  if FActive then
    EnumerateNet(FItems, nil);
end;    procedure TNetworkBrowser.SetActive(Value: Boolean);
begin
  if Value <> FActive then
  begin
    FActive := Value;
    Refresh;
  end;
end;    procedure TNetworkBrowser.SetScope(Value: TNetScope);
begin
  if Value <> FScope then
  begin
    FScope := Value;
    Refresh;
  end;
end;    procedure TNetworkBrowser.SetResourceType(Value: TNetResourceType);
begin
  if Value <> FResourceType then
  begin
    FResourceType := Value;
    Refresh;
  end;
end;    procedure TNetworkBrowser.SetUsage(Value: TNetUsage);
begin
  if Value <> FUsage then
  begin
    FUsage := Value;
    Refresh;
  end;
end;    procedure TNetworkBrowser.Open;
begin
  Active := True;
end;    procedure TNetworkBrowser.Close;
begin
  Active := False;
end;    
噓~~~~~~沉思中…
hagar
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#5 引用回覆 回覆 發表時間:2002-08-22 08:25:13 IP:211.22.xxx.xxx 未訂閱
小弟遇到如下的問題:
unit NetBrwsr;    interface    uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs;    type
  TNetScope = (nsConnected, nsGlobal, nsRemembered, nsContext);
  TNetResourceType = (nrAny, nrDisk, nrPrint);
  TNetDisplay = (ndDomain, ndGeneric, ndServer, ndShare, ndFile, ndGroup,
    ndNetwork, ndRoot, ndShareAdmin, ndDirectory, ndTree, ndNDSContainer);
  TNetUsage = set of (nuConnectable, nuContainer);      TNetworkItems = class;      TNetworkItem = class
  private
    FScope: TNetScope;
    FResourceType: TNetResourceType;
    FDisplay: TNetDisplay;
    FUsage: TNetUsage;
    FLocalName: string;
    FRemoteName: string;
    FComment: string;
    FProvider: string;
    FSubItems: TNetworkItems;
  public
    constructor Create;
    destructor Destroy; override;
    property Scope: TNetScope read FScope;
    property ResourceType: TNetResourceType read FResourceType;
    property Display: TNetDisplay read FDisplay;
    property Usage: TNetUsage read FUsage;
    property LocalName: string read FLocalName;
    property RemoteName: string read FRemoteName;
    property Comment: string read FComment;
    property Provider: string read FProvider;
    property SubItems: TNetworkItems read FSubItems;
  end;      TNetworkItems = class
  private
    FList: TList;
    procedure SetItem(Index: Integer; Value: TNetworkItem);
    function GetItem(Index: Integer): TNetworkItem;
    function GetCount: Integer;
  public
    constructor Create;
    destructor Destroy; override;
    procedure Clear;
    procedure Add(Item: TNetworkItem);
    procedure Delete(Index: Integer);
    property Items[Index: Integer]: TNetworkItem read GetItem write
    SetItem; default;
    property Count: Integer read GetCount;
  end;      TNetworkBrowser = class(TComponent)
  private
    FItems: TNetworkItems;
    FScope: TNetScope;
    FResourceType: TNetResourceType;
    FUsage: TNetUsage;
    FActive: Boolean;
    procedure Refresh;
    procedure SetActive(Value: Boolean);
    procedure SetScope(Value: TNetScope);
    procedure SetResourceType(Value: TNetResourceType);
    procedure SetUsage(Value: TNetUsage);
    procedure EnumerateNet(NetItems: TNetworkItems; lpnr: PNetResource);
  protected
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
    procedure Open;
    procedure Close;
    property Items: TNetworkItems read FItems;
  published
    property Scope: TNetScope read FScope write SetScope default nsGlobal;
    property ResourceType: TNetResourceType read FResourceType
      write SetResourceType default nrAny;
    property Usage: TNetUsage read FUsage write SetUsage default [];
    property Active: Boolean read FActive write SetActive default False;
  end;    implementation    type
  PNetResourceArray = ^TNetResourceArray;
  TNetResourceArray = array[0..0] of TNetResource;    { TNetworkItem }    constructor TNetworkItem.Create;
begin
  inherited;
  FSubItems := TNetworkItems.Create;
end;    destructor TNetworkItem.Destroy;
begin
  if FSubItems <> nil then
    FSubItems.Free;
  inherited;
end;    { TNetworkItems }    constructor TNetworkItems.Create;
begin
  inherited;
  FList := TList.Create;
end;    destructor TNetworkItems.Destroy;
begin
  Clear;
  if FList <> nil then
    FList.Free;
  inherited;
end;    procedure TNetworkItems.SetItem(Index: Integer; Value: TNetworkItem);
begin
  if (FList.Items[Index] <> nil) and (FList.Items[Index] <> Value) then
    TNetworkItem(FList.Items[Index]).Free;
  FList.Items[Index] := Value;
end;    function TNetworkItems.GetItem(Index: Integer): TNetworkItem;
begin
  Result := TNetworkItem(FList.Items[Index]);
end;    procedure TNetworkItems.Clear;
begin
  while Count > 0 do
    Delete(0);
end;    procedure TNetworkItems.Add(Item: TNetworkItem);
begin
  FList.Add(Item);
end;    procedure TNetworkItems.Delete(Index: Integer);
begin
  if FList.Items[Index] <> nil then
    TNetworkItem(FList.Items[Index]).Free;
  FList.Delete(Index);
end;    function TNetworkItems.GetCount: Integer;
begin
  if FList <> nil then
    Result := FList.Count
  else
    Result := 0;
end;    { TNetworkBrowser }    constructor TNetworkBrowser.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  FItems := TNetworkItems.Create;
  FScope := nsGlobal;
  FResourceType := nrAny;
  FUsage := [];
end;    destructor TNetworkBrowser.Destroy;
begin
  if FItems <> nil then
    FItems.Free;
  inherited;
end;    procedure TNetworkBrowser.EnumerateNet(NetItems: TNetworkItems; lpnr:
  PNetResource);
var
  dwResult, dwResultEnum: Integer;
  hEnum: THandle;
  cbBuffer, cEntries, i: Integer;

  cbBuffer, cEntries 要宣告成 Cardinal 型態      nrArray: PNetResourceArray;
  NewItem: TNetworkItem;
  dwScope, dwType, dwUsage: Integer;
begin
  cbBuffer := 16384;
  cEntries := $FFFFFFFF;      case FScope of
    nsConnected: dwScope := RESOURCE_CONNECTED;
    nsGlobal: dwScope := RESOURCE_GLOBALNET;
    nsRemembered: dwScope := RESOURCE_REMEMBERED;
    nsContext: dwScope := RESOURCE_CONTEXT;
  else
    dwScope := RESOURCE_GLOBALNET;
  end;
  case FResourceType of
    nrAny: dwType := RESOURCETYPE_ANY;
    nrDisk: dwType := RESOURCETYPE_DISK;
    nrPrint: dwType := RESOURCETYPE_PRINT;
  else
    dwType := RESOURCETYPE_ANY;
  end;
  dwUsage := 0;
  if nuConnectable in FUsage then
    dwUsage := dwUsage or RESOURCEUSAGE_CONNECTABLE;
  if nuContainer in FUsage then
    dwUsage := dwUsage or RESOURCEUSAGE_CONTAINER;      dwResult := WNetOpenEnum(dwScope, dwType, dwUsage, lpnr, hEnum);
  if dwResult <> NO_ERROR then Exit;      GetMem(nrArray, cbBuffer);
  repeat
    dwResultEnum := WNetEnumResource(hEnum, cEntries, nrArray, cbBuffer);      上述 cbBuffer, cEntries 兩個變數如果宣告成 integer
  在上面這行會出現錯誤訊息        if dwResultEnum = NO_ERROR then
      for i := 0 to cEntries - 1 do
      begin
        NewItem := TNetworkItem.Create;
        case nrArray[i].dwScope of      在這上面這一行會出現如下的錯誤訊息:
  Record, Object or Class Type required
  請問一下大家, 要如何解?              RESOURCE_CONNECTED: NewItem.FScope := nsConnected;
          RESOURCE_GLOBALNET: NewItem.FScope := nsGlobal;
          RESOURCE_REMEMBERED: NewItem.FScope := nsRemembered;
          RESOURCE_CONTEXT: NewItem.FScope := nsContext;
        else
          NewItem.FScope := nsGlobal;
        end;
Clarinet
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#6 引用回覆 回覆 發表時間:2002-08-22 09:27:44 IP:218.32.xxx.xxx 未訂閱
引言: 小弟遇到如下的問題: //恕以下刪除
hagar版主大人您好! 我沒有實際測試過,所以您自行試試看下列的作法。 將 cbBuffer, cEntries 宣告成 Cardinal 型態,然後在 ....... repeat cEntries :=dword(-1);//加入這一行即可 dwResultEnum := WNetEnumResource(hEnum, cEntries, nrArray, cbBuffer); ........ ............. 請您自行試試看吧! GPS(全球衛星定位系統) http://www.allgps.com
------
GPS(全球衛星定位系統)
http://www.allgps.com
系統時間:2024-05-04 7:48:42
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