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 How to work with WMI services to access
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WMI is a very useful interface accessible through DesktopX via scripting to retrieve all sort of information from the operating system. It opens the door for new useful widgets.
You can find here the full MSDN documentation, in particular the introduction: Windows Management Instrumentation.

Write a Free Memory Object that uses WMI.

  • Create a new text object.
  • Create a new script.
  • Declare a global variable like this:

Dim objWMIService

  • This variable will hold the WMI provider. We initialize it on Object_OnScriptEnter and delete it on Object_OnScriptEnter. Since we are making an object that polls through WMI useful information, we will have the WMI service object always available for the object lifetime. You can find more information on MSDN about the actual syntax to create an instance. GetObject("winmgmts:\\.\root\cimv2") just means you are creating a WMI instance to query information in the cimv2 category for the local machine (\.\).

Sub Object_OnScriptEnter
Set objWMIService = GetObject("winmgmts:\\.\root\cimv2")
object.settimer 123, 5000
Object_OnTimer123 'let's update it immediately
End Sub

Sub Object_OnScriptExit
'Let's clean it, as a good practice
Set objWMIService = nothing
End Sub

  • Now it is time to query WMI for getting some information. We are asking here for available system memory.

Sub Object_OnTimer123
Dim colItems
Set colItems = objWMIService.ExecQuery("Select AvailableMBytes from Win32_PerfFormattedData_PerfOS_Memory",,48)
For Each objItem In colItems
Object.text = "Available memory: " & objItem.AvailableMBytes & " MB"
'we just really need one result here, so we exit
Exit Sub
Next
End Sub


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