【摘要】 在开发一个实际的系统中,利用面向对象的思想,对地图制图对象进行了分类,从地图制图对象中抽象出多个地图制图用的GIS20对象类,并充分利用面向对象的继承和多态性,实现了地图的制图输出、图层管理和文件存储等功能。文章对这些内容作了概要介绍。更多还原

【Abstract】 In this thesis, the cartography objects have been classified in the exploitation of a practical GIS system using the idea of object- oriented programming. By fully utilizing the inheritance and polymorphism of OOP, the cartography output, map layer management and files saving have been realized after the abstraction of more than twenty classes from the cartography objects.更多还原