var
WorkgroupCount : Integer;
Workgroup: Array[1..500] of String[25];

Procedure FindAllWorkgroups;
Var
EnumHandle: THandle;
EntireNetwork: TNetResource;
Buf: Array[1..500] of TNetResource;
BufSize: Integer; // 或DWORD;
Entries: Integer; // 或DWORD;

begin
FillChar(EntireNetwork, SizeOf(EntireNetwork) , 0);
With EntireNetwork do begin
dwScope := 2;
dwDisplayType := 6;
dwUsage := 2;
end;

WNetOpenEnum( RESOURCE_GLOBALNET,
RESOURCETYPE_ANY,
0,
@EntireNetwork,
EnumHandle );

WorkgroupCount := 0;
Repeat
Entries := 1;
BufSize := SizeOf(Buf);

WNetEnumResource( EnumHandle,
Entries,
@Buf,
BufSize );
If Entries = 1 then begin
Inc( WorkgroupCount );
Workgroup[ WorkgroupCount ] := StrPas(Buf[1].lpRemoteName);
end;
Until (Entries <> 1);

WNetCloseEnum( EnumHandle );
end;

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