The WNetOpenEnum function starts an enumeration of network resources or existing connections.
DWORD WNetOpenEnum(
|
DWORD dwScope, |
// scope of enumeration |
|
DWORD dwType, |
// resource types to list |
|
DWORD dwUsage, |
// resource usage to list |
|
LPNETRESOURCE lpNetResource, |
// pointer to resource structure |
|
LPHANDLE lphEnum |
// pointer to enumeration handle buffer |
|
); |
|
Value |
Meaning |
|
RESOURCE_CONNECTED |
All currently connected resources (the dwUsage parameter is ignored). |
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RESOURCE_CONTEXT |
Only resources in the network context of the caller (used for a Network Neighborhood view). The dwUsage parameter is ignored. |
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RESOURCE_GLOBALNET |
All resources on the network. |
|
RESOURCE_REMEMBERED |
All remembered (persistent) connections (the dwUsage parameter is ignored). |
|
Value |
Meaning |
|
RESOURCETYPE_ANY |
All resources (this value cannot be combined with RESOURCETYPE_DISK or RESOURCETYPE_PRINT). |
|
RESOURCETYPE_DISK |
All disk resources. |
|
RESOURCETYPE_PRINT |
All print resources. |
If a network provider cannot distinguish between print and disk resources, it
may enumerate all resources.
|
Value |
Meaning |
|
0 |
All resources |
|
RESOURCEUSAGE_CONNECTABLE |
All connectable resources |
|
RESOURCEUSAGE_CONTAINER |
All container resources |
This parameter is ignored if the dwScope parameter is not
RESOURCE_GLOBALNET.
If this parameter is NULL, the root of the network is assumed. Windows organizes a network as a hierarchy; the root is the topmost container in the network.
If this parameter is not NULL, it must point to a NETRESOURCE structure. This structure can be filled in by the application or be returned by a call to the WNetEnumResource function. The NETRESOURCE structure must specify a container resource; that is, the RESOURCEUSAGE_CONTAINER value must be specified in the dwUsage member.
To enumerate all network resources, an application can begin the enumeration by calling WNetOpenEnum with lpNetResource set to NULL and then use the returned handle with WNetEnumResource to enumerate resources. If one of the resources in the NETRESOURCE array returned by the WNetEnumResource function is a container resource, WNetOpenEnum can be used to open the resource for further enumeration.
If the dwScope parameter is not RESOURCE_GLOBALNET, this parameter must
be NULL.
If the function succeeds, the return value is NO_ERROR.
If the function fails, the return value is an error code. To get extended error information, call GetLastError. GetLastError may return one of the following error codes:
|
Value |
Meaning |
|
ERROR_NOT_CONTAINER |
The lpNetResource parameter does not point to a container. |
|
ERROR_INVALID_PARAMETER |
Either the dwScope or dwType parameter is invalid, or there is a bad combination of parameters. |
|
ERROR_NO_NETWORK |
No network is present. |
|
ERROR_EXTENDED_ERROR |
A network-specific error occurred. To get a description of the error, use the WNetGetLastError function. |
The function returns error codes for compatibility with Windows version 3.1. For compatibility with Windows NT, the function also sets the error code value returned by GetLastError.
The exact interpretation of RESOURCE_CONTEXT in the dwScope parameter depends on the networks installed on the machine.
The WNetOpenEnum function is used to begin enumeration of the resources in a single container. The following examples show the hierarchical structure of a Microsoft LAN Manager network and a Novell Netware network:
LanMan (container, in this case the provider) ACCOUNTING (container, in this case the domain) \\ACCTSPAY (container, in this case the server) PAYFILES (disk) LASERJET (print) Netware (container, in this case the provider) MARKETING (container, in this case the server) SYS (disk, first one on any Netware server) ANOTHERVOLUME (disk) LASERJET (print)
NETRESOURCE, WNetCloseEnum, WNetEnumResource, WNetGetLastError
Code: