Enumerate list of network computers and shared fol

Question

I know there's plenty ways of enumerating computers and devices on a network, but how do I show just computers available for Windows file sharing? I need to provide a tree view of network computers and their shared folders. I know I could use existing shell controls for this, but I would rather keep it in my own tree view. It will only list those computers on the network which have shared folders. Past the computers and their shared folders, I can do the individual directory listing part myself. I just need to know how to get the computer list and their shared folder lists.

Answer 1

WNetOpenEnum will give you all the computers on the network

The WNetOpenEnum function starts an enumeration of network resources or existing connections. You can continue the enumeration by calling the WNetEnumResource function.

NetShareEnum will you all shares on a machine.

Retrieves information about each shared resource on a server.

You can use the combination of both to filter out what you don't want

Answer 2

Please consider the following resources if you are interested in sample Delphi code using WNetOpenEnum/WNetOpenEnum Windows API:

• Networked Drives by Angus John:
• Use the Windows API to generate a list of available Network Resources published in the EDN by Justin Swett
• Get a list of computers in a network from Delphitricks.com.

Having a good command of NETRESOURCE structure is also must.

I personnaly recommend the following listings from http://www.developpez.net's Forum:

Listing #1:

---

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Unit2;

type
  TForm1 = class(TForm)
    ListBox1: TListBox;
    procedure FormCreate(Sender: TObject);
  private
    procedure EnumNetworkProc(const aNetResource :TNetResource; const aLevel :word; var aContinue :boolean);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

{ TForm1 }

procedure TForm1.EnumNetworkProc(const aNetResource :TNetResource; const aLevel :word; var aContinue :boolean);
begin
  if aNetResource.dwDisplayType in [RESOURCEDISPLAYTYPE_DOMAIN, RESOURCEDISPLAYTYPE_SERVER] then
    ListBox1.Items.Add(StringOfChar(' ', aLevel*4) +aNetResource.lpRemoteName);
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  EnumNetwork(EnumNetworkProc, RESOURCE_GLOBALNET, RESOURCETYPE_DISK);
end;

end.

---

Listing #2:

unit Unit2;

interface

uses Windows;

type
  TEnumNetworkProc = procedure(const aNetResource :TNetResource; const aLevel :word; var aContinue :boolean) of object;

procedure EnumNetwork(const aEnumNetworkProc :TEnumNetworkProc; const aScope :dword = RESOURCE_GLOBALNET; const aType :dword = RESOURCETYPE_ANY);

implementation

//Procédure récursive
procedure DoEnumNetwork(const aContainer :Pointer;
                        const aEnumNetworkProc :TEnumNetworkProc;
                        const aScope :dword;
                        const aType  :dword;
                        const aLevel :byte);
type
  PNetResourceArray = ^TNetResourceArray;
  TNetResourceArray = array [0..0] of TNetResource;
var
  NetHandle    :THandle;
  NetResources :PNetResourceArray;
  NetResult    :dword;
  Size, Count, i :Cardinal;
  Continue     :boolean;
begin
  Continue := TRUE;

  NetResult := WNetOpenEnum(aScope, aType, 0, aContainer, NetHandle);

  if NetResult = NO_ERROR then
  try
    //Taille de base
    Size := 50 *SizeOf(TNetResource);
    GetMem(NetResources, Size);

    try
      while Continue do
      begin
        Count := $FFFFFFFF;
        NetResult := WNetEnumResource(NetHandle, Count, NetResources, Size);

        //Taille insuffisante ?
        if NetResult = ERROR_MORE_DATA
        then ReallocMem(NetResources, Size)
        else Break;
      end;

      //Enumère
      if NetResult = NO_ERROR then
        for i := 0 to Count - 1 do
        begin
          //Callback
          if Assigned(aEnumNetworkProc) then
          begin
            aEnumNetworkProc(NetResources^[i], aLevel, Continue);
            if not Continue then Break;
          end;

          //Appel récursif
          if (NetResources^[i].dwUsage and RESOURCEUSAGE_CONTAINER) > 0 then 
            DoEnumNetwork(@NetResources^[i], aEnumNetworkProc, aScope, aType, aLevel +1);
        end;
    finally
      FreeMem(NetResources, Size);
    end;
  finally
    WNetCloseEnum(NetHandle);
  end;
end;

procedure EnumNetwork(const aEnumNetworkProc: TEnumNetworkProc; const aScope, aType: dword);
begin
  DoEnumNetwork(nil, aEnumNetworkProc, aScope, aType, 0);
end;

end.

---

Source: Liste des machines sur un réseau local (tout le réseau de Win) - Original post (in French) by Lucas Panny.