I have a layer of regions (25 regions) and a layer with thousands of polygons. I want to dissolve this into one polygon for each region (so I can calculate the exact geometry). I used the dissolve tool of ArcGIS, but using this dissolves it into one layer. Is there a trick for this? Can't seem to see it in the dissolve tool itself.
You should be able to do that by using two tools, Dissolve and Split:
- First of all, add field for region in polygon attribute table. This field must be text-type.
- After that, dissolve your polygon layer but remember to check Create multipart features (it is optional) but by default it is checked.
- Finally, split same region in different layer by Split(Analysis) tools in Arctoolbox in specific Workspace. Split Field in Split(Analysis) is the field region you had created already.