How to execute an action based on registry values?
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I am having following registry key

    $rKey="hklm:\SOFTWARE\Wow6432Node\Mycompany\MyProj\Core"

 
This key will be having following parameters

     DBServer="Installed"
     AppServer="Installed"
     WebServer="Installed"

I would like to check 

     if DBserver="Installed" Then do some action
     Else Do nothing

     If Appserver="Installe" then do some action
     Else Do nothing

     If Webserver ="Installed" then do some action
     Else Do nothing

How to get value of property and execute action based on it?