Blank spaces in the map to a feature class in arcmap

[Maya007]

Hello,

I have some basic doubts in Arc-Map. Please answer

I want to convert the blank spaces within the map into another feature class. How could that be done?

I have roads and forests in the map now. I want the remaining blank spaces to be like a feature class like polygons or even as raster. How is it possible?

I tried by making a feature class (polygon) covering entire study area and then subtracted roads and forests from this using raster calculator. I then realized it doesn't subtract spatially instead based on the attribute values  

 

 

Edited February 21, 2018 by Maya007

[mostafa]

create a new rectangle polygon around study area then select all feature classes from the source layer then merge (if there is too many features and you want subtract all in one step) then select the source layer that you merged it and clip to rectangle polygon layer.

 

[Maya007]

Thanks a lot Mostafa Will try that for sure