MicroSoft提供了以下几个API：WnetOpenEnum、WnetEnumResource、WNetCloseEnum及一个结构类型NETRESOURCE用于搜索局域网上的网络资源。

其中NETRESOURCE的定义如下:

typedef struct _NETRESOURCE { // nr

　DWORD dwScope;

　DWORD dwType;

　DWORD dwDisplayType;

　DWORD dwUsage;

　LPTSTR lpLocalName;

　LPTSTR lpRemoteName;

　LPTSTR lpComment;

　LPTSTR lpProvider;

} NETRESOURCE; 

我们主要用到是dwType(资源类型：磁盘或打印机)、dwDisplayType(资源类型：服务器，域等)、dwUsage(判断是不是容器container)、lpRemoteName(资源名称)。

WnetOpenEnum的作用是打开某一特定的资源容器句柄给WnetEnumResource。WnetEnumResource枚举出指定容器下所有网络资源。

下面是一个列出所有网络资源的的函数示例:

bool __fastcall TForm1::EnumerateFunc(HWND hwnd ,LPNETRESOURCE lpnr,TTreeNode * ParentNode)

{

DWORD dwResult, dwResultEnum;

HANDLE hEnum;

DWORD cbBuffer = 16384; /* 16K is reasonable size */

DWORD cEntries = 0xFFFFFFFF; /* enumerate all possible entries */

LPNETRESOURCE lpnrLocal; /* pointer to enumerated structures */

DWORD i;

dwResult = WNetOpenEnum(RESOURCE_GLOBALNET,

RESOURCETYPE_ANY,

0, /* enumerate all resources */

lpnr, /* NULL first time this function is called */

&hEnum); /* handle to resource */

if (dwResult ==67) //domain下没有可访问的主机

return true;

if (dwResult != NO_ERROR ) { //无

ShowError(dwResult);

return false;

}

TTreeNode * Child;

do {

lpnrLocal = (LPNETRESOURCE) GlobalAlloc(GPTR, cbBuffer);

dwResultEnum = WNetEnumResource(hEnum, /* resource handle */

&cEntries, /* defined locally as 0xFFFFFFFF */

lpnrLocal, /* LPNETRESOURCE */

&cbBuffer); /* buffer size */

if (dwResultEnum == NO_ERROR) {

for(i = 0; i < cEntries; i++) {

Child=TreeView1->Items->AddChild(ParentNode,lpnrLocal[i].lpRemoteName);

if(RESOURCEUSAGE_c o nTAINER ==

(lpnrLocal[i].dwUsage & RESOURCEUSAGE_c o nTAINER))

if(!EnumerateFunc(this->Handle, &lpnrLocal[i],Child))

ShowMessage("EnumerateFunc returned FALSE.");

}

}

else if (dwResultEnum != ERROR_NO_MORE_ITEMS) {

ShowError(dwResultEnum);

break;

}

}

while(dwResultEnum != ERROR_NO_MORE_ITEMS);

GlobalFree((HGLOBAL) lpnrLocal);

dwResult = WNetCloseEnum(hEnum);

if(dwResult != NO_ERROR) {

ShowError(dwResult);

return FALSE;

}

return true;

}