arcgis 10.0 - How to assign node IDs to links in a network?

I have two shapefile layers in ArcGIS for Desktop 10.

I have one line layer and node layer.

My node layer(shp) has a "code_1" field and line layer has a "code_node" field.

The intersection point of the line layer has only one node.

I want get the code from the "code_1" field of the node layer for the line's "code_node" field

For example, for one line, the first node has code_1=1 and the node at the end of line has code_1=2. In this case the code_node attribute in that line must be "12",.

How can I automatically get the code from the nodes for each line?