Select structure by coordinate

[luiz.silvaNDFA2]

Good afternoon, first I'm sorry for English because I don't know how to speak. I am developing a routine in C # to build a network from data that is in .txt. The big problem is that I need to check if there is a structure before inserting a new one, if I have to pick it up. I've tried to use all forms of selection such as: SelectFence, electCrossingWindow ... and I can't get the structure that has already been launched. Does anybody know how to solve this?

[KirkWM]

You could do this with Dyanmo and use the Civil nodes to harvest all the existing structure insertion points and use those coordinates to filter the list of structures to be imported. You could even put a bounding box as a buffer around the existing points and intersect them with the import list incase they are not exactly the same. Feel free to come check out the Dynamo for Civil 3D fourm to get some ideas: https://forum.dynamobim.com/c/civil3d/17  

[luiz.silvaNDFA2]

The bad thing is that I don't know Dynamo and I don't know how to do the interaction between Dynamo and C #