combine multiple tracesource filters in app.config
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I want to configure a FileTraceListeners in my application, that ignores 'verbose' level messages but logs 'information' level and above as well as 'start' and 'stop' events.

Everything is configured within the app.config file.
However I cannot find the correct syntax for combining these different trace levels. 
[The Syntax for filters is explained here][1]. 

Using a single filter for 'information' will correctly filter out everything that is not 'information', 'warning' 'error' or 'critical'. However I also want to include 'start' and 'stop' events.

I tried using 2 filters :

<!-- language: lang-xml -->

    <filter type="System.Diagnostics.EventTypeFilter" initializeData="Information"/>
    <filter type="System.Diagnostics.EventTypeFilter" initializeData="ActivityTracing"/>

I tried combining the initializeDate 

with commas:
`initializeData="Information,ActivityTracing"` 

or semicolons  `initializeData="Information;ActivityTracing"`

everything will just cause a syntax error.

How do I combine these two filters?


(I am using the native .net 3.5 logging libraries and do not wish to change to log4net or another framework at this point.)


  [1]: http://msdn.microsoft.com/en-us/library/ms229326.aspx