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Dashed border off adjacent polygons

May 24 2010 | 1 comment
Categories: Symbology

Good afternoon,
I have a feature class of polygons that I want to symbolize with dashed lines. Unfortunately, the lines that are borders of adjacent polygons were drawn without regard to orientation, and now the dashes (6, 2 proportion) overdraw each other in areas of the map (see attached).
Is there an easy way to fix the representation or line orientation so that the dashes line up?

Thanks for all of your help.

Mapping Center Answer:

One solution is to convert the polygon features to line features and then symbolize the lines.  We wrote this up for the Oregon Earthquakes map:

If your map has a solid color background, here is a solution that was posted on this thread (

"Another way to handle symbology on the redundant (duplicated) polygon edges where polygons meet is to create a two layer-linesymbol with a solid bottom layer symbolised as the background color of the map. On top of that one, you define the desired pattern for your boundaries. This approach will mask out the first edge when the second edge draws on top!" (Thanks to Bengt Lundstrom for this idea!)

To make the resulting dashed lines look even better in either case, use convert them to cartographic representations and set the properties for the dashed lines so that they stop and start the same.

Thanks for the reply posted by David VandenBos on Jun 1 2010 6:14AM
Thank you for your time to reply. I appreciate your willingness to answer the same question several times for us. I ended up converting to lines and using representations (since I didn't have a solid colored background).

Thanks again.

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