editinglineqgissplittingvertices
I've searched a lot but didn't find an answer: When editing lines with QGIS, I often need to split a linestring exactly on one of his existing internal vertices, but I can't find a way.
I've tried the tool "Split Features" thinking that it could snap on vertices, but I was wrong, and I've tried several ways of selecting the vertex with no luck… Any solution?
I would probably use IPolyCurve.SplitAtPoint and get the paths (parts) created after the split and do your processing on those. As long as the createPart argument is true, SplitAtPoint doesn't just add a new vertex, it inserts a new part between the split point and the end of the path.
(source: arcgis.com)
Whether this is the best approach somewhat depends on what processing you need to do however.
Best Answer
In Snapping Options (Settings menu) enable snapping (better snapping to vertex only in your case as suggested in comments) for your layer, then using Split feature tool make a left click on the one blank space on side of the line, then make left click on the vertex where the split should occur and in the end make a right click on the blank space on the other side of the line.