[OpenLayers-Users] thoughts on a design pattern for a common vector layer task

[Puneet Kishor]

I tend to do something like so a lot

1. listen to a map event
2. on event, get data from server
3. create vector layer "foo" unless vector layer "foo" already exists
4. add the data from #2 to vector layer "foo"


What is the most efficient way to achieve the above? Where I get lost is #3 above. 
How do I determine if a particular layer exists?
If it does, should I delete it, and recreate it, or should I delete all the features on it and add new features to it?



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Puneet Kishor