读取点线连接，使用类迪杰斯特拉算法求解最短路径输出服务区范围，并通过nodejs搭建服务器，在网页上用canvas绘制显示。原始数据中，点数据为（ID，坐标xy）线数据为（前后连接点，权值）-Read point line connection using class Dijkstra shortest path algorithm output service area, and set up the server through nodejs, drawn with canvas on the page, raw data, point data (ID, coordinates xy) line data is (before and after the connection point, weights)