地图符号动态库调用源码 本软件包给出了的Vc++6.0和Delphi7.0的调用例子程序和动态库接口说明，在例子中可使用鼠标滚动实现图形的放大和缩小，鼠标拖动实现漫游,Map symbol dynamic library call to give the source of this package of Vc++6.0 and Delphi7.0 example program call and dynamic library interface that can be used in th