WMI是一项行业推荐规范，旨在为访问企业环境中的管理信息而开发一种标准化技术。该信息包括系统内存的状态、当前安装的客户应用程序清单，以及有关客户端状态的其他数据。
WMI是可伸缩的系统管理结构，该规范采用一个统一、基于标准且可扩展的面向对象接口。它提供与系统管理员信息和基础WMI API交互的标准方法，主要由系统管理应用程序开发人员和系统管理员用来访问和操作系统管理信息。
WMI可用来生成组织和管理系统信息的工具，使系统管理人员能够更密切的监视系统活动。
WMI提供了一套内置在Microsoft Windows操作系统中的丰富的系统管理服务，现在有大量的应用程序、服务和设备用其为信息技术操作和产品支持组织提供全方位的管理功能。基于WMI的管理系统的使用带来了更可靠的计算环境和更高的系统可靠性，从而节省了企业的开销。
WMI提供的大量的规范为许多高端应用程序，例如Microsoft Exchange、Microsoft SQL Server和Microsoft Internet信息服务(IIS)等实现如下管理任务。
1． 监视应用程序的运行情况
2． 检测瓶颈或故障
3． 管理和配置应用程序
4． 查询应用程序数据(使用对象关系的遍历和查询)
5． 执行无缝的本地或远程管理操作
下面我们通过一个例子来说明WMI的强大功能。以vb6为列：
引用”Microsoft WMI Scripting V1.1 Library”
代码如下:
Option Explicit
Dim WithEvents Sink As SWbemSink
Dim j As Integer
'功能:利用wmi组件得到计算机的信息,每一个小功能分开写，便于大家查阅
Private Sub cmdDone_Click()
Dim oWMINameSpace As SWbemServices
Dim oLogicalDiskSet As SWbemObjectSet
Dim oLogicalDisk As SWbemObject
Dim ObjSet As Variant
Dim sDrive As String
Dim sValue As String
Dim dblSize As Double
Dim Obj As Variant
Dim lIndex As Long
Set oWMINameSpace = GetObject("winmgmts:")
'得到驱动器的信息
On Error Resume Next
Set ObjSet = oWMINameSpace.InstancesOf("Win32_DiskDrive")
For Each Obj In ObjSet
List5.AddItem Obj.Caption & " - " & BytesToMegabytes(Obj.Size) & " GB"
Next
'得到每一个驱动器的详细信息
On Error GoTo ErrorHandler
'Set oWMINameSpace = GetObject("winmgmts:")
Set oLogicalDiskSet = oWMINameSpace.InstancesOf("Win32_LogicalDisk")
For Each oLogicalDisk In oLogicalDiskSet
On Error Resume Next
sDrive = oLogicalDisk.deviceid
ListView1.ListItems.Add , , sDrive
lIndex = ListView1.ListItems.Count
sValue = oLogicalDisk.Description & ""
ListView1.ListItems(lIndex).SubItems(1) = sValue
sValue = oLogicalDisk.FileSystem & ""
ListView1.ListItems(lIndex).SubItems(2) = sValue
sValue = oLogicalDisk.VolumeName & ""
ListView1.ListItems(lIndex).SubItems(3) = sValue
sValue = oLogicalDisk.VolumeSerialNumber & ""
ListView1.ListItems(lIndex).SubItems(4) = sValue
sValue = oLogicalDisk.Size & ""
If IsNumeric(sValue) Then
dblSize = BytesToMegabytes(CDbl(sValue))
sValue = CStr(dblSize) & " MB"
End If
ListView1.ListItems(lIndex).SubItems(5) = sValue
Next
CleanUp:
Set oLogicalDisk = Nothing
Set oLogicalDiskSet = Nothing
Set oWMINameSpace = Nothing
Exit Sub
ErrorHandler:
MsgBox "" & Err.Description
GoTo CleanUp
End Sub
Private Sub Command1_Click()
Unload Me
End Sub
Private Function BytesToMegabytes(Bytes As Double) As Double
Dim dblAns As Double
dblAns = (Bytes / 1024) / 1024
BytesToMegabytes = Format(dblAns, "###,###,##0.00")
End Function
Private Sub Command2_Click()
Dim oWMINameSpace As SWbemServices
Dim SystemSet As Variant
Dim System As Variant
Dim ObjSet As Variant
Dim Obj As Variant
Set oWMINameSpace = GetObject("winmgmts:")
'操作系统
Set SystemSet = oWMINameSpace.InstancesOf("Win32_OperatingSystem")
For Each System In SystemSet
List1.AddItem System.Caption
List1.AddItem System.Manufacturer
List1.AddItem System.BuildType & “” ‘Win9x下好像取不出来
List1.AddItem System.Version
List1.AddItem System.SerialNumber
Next
'cpu
Set ObjSet = oWMINameSpace.InstancesOf("Win32_Processor")
For Each Obj In ObjSet
List2.AddItem Obj.Caption
List2.AddItem Obj.currentclockspeed & " Mhz"
Next
End Sub
Private Sub Command3_Click()
Dim oWMINameSpace As SWbemServices
Dim ObjSet As Variant
Dim Obj As Variant
Dim Adapter As Variant
'内存
Set oWMINameSpace = GetObject("winmgmts:")
Set ObjSet = oWMINameSpace.InstancesOf("Win32_PhysicalMemory")
Dim i As String
For Each Obj In ObjSet
List3.AddItem BytesToMegabytes(Obj.capacity) & " MB" & " Chip"
Next
'网卡
Set Sink = New SWbemSink
Set Adapter = GetObject("winmgmts:")
Adapter.InstancesOfAsync Sink, "Win32_NetworkAdapter"
End Sub
Private Sub Form_Load()
j = 0
End Sub
Private Sub Sink_OnObjectReady(ByVal objWbemObject As WbemScripting.ISWbemObject, ByVal objWbemAsyncContext As WbemScripting.ISWbemNamedValueSet)
Dim Adapter As Variant
‘得到所有的适配器信息
Set Adapter = GetObject("winmgmts:Win32_NetworkAdapterConfiguration=" & j & "")
List4.AddItem Adapter.Description
If IsNull(Adapter.MACAddress) Then
List4.AddItem "No MAC Address"
List4.AddItem ""
Else
List4.AddItem "Mac: " & Adapter.MACAddress
List4.AddItem ""
End If
j = j + 1
End Sub
当执行后，出现如下所示:
是不是感到了WMI功能的强大。注明：Windows2000/XP已经安装了WMI。Win98默认不支持，需要安装WMI For Win9x驱动。
