I have a Sidewalks layer (polyline) and an Map Grid Index layer (polygon) that I need to get data into. I am trying to calculate the total LF of sidewalks in a particular Map Grid by centroid. So, as long as the centroid of the sidewalk is in a particular map grid it will calculate and add a field to the Polygon layer. I know how much sidewalk I have in the area and there's around 400 or so Grids I need to fill out. I don't want to do it manually for all 400 grids. Any help would be appreciated! Hopefully this makes sense! Thanks for the help!