Aug 8, 2009 at 1:04 PM
Edited Aug 8, 2009 at 1:54 PM
Hi firash, you will need to look at routing algorithms such as "A Star", there are implementations in a few libraries such as QuickGraph and NGenerics.
You will need to convert your data into a directed network,
Find a way to snap the start and end points on the map to a node/edge end in the network
run the algorithm
It may also be worth taking a look at NetTopologySuite as Diego Guidi was working in this area with it