I am using ArcMap 10.2 and merging several line segments with the same ID. Most of the time this works fine and I end up with one segment. (about 95% of the time)
However, occasionally the segments will merge but I end up with two separate "parts". The "parts" I am speaking of are what you can see when you "edit vertices" and look to the "Edit Sketch Properties". It says "Part 0" ….lists all vertices…"Part 1"…lists all vertices
The end goal is building "M" values for these merged segments and I haven't found a workaround other than splitting the merged segment before the second "part" starts and extend/tracing over the original part that wouldn't merge properly. This is becoming very tedious with larger segments.
Best Answer
Using the Dissolve (Data Management) tool on your ID field for your lines, you can specify whether the resultant lines will be multi-part or single-part via the multi-part parameter. You can also dissolve or unsplit lines via the unsplit parameter.