实现梯形图编辑功能的新方法

A New Approach to Achieving the Edit Function of Ladder Graphics

采用Ｃ语言实现内装型ＰＭＣ梯形图绘制和编辑功能，使软件整体结构紧凑，可靠性高．使用双向链表数据结构描述和记录梯形图的各种信息，以实现汉字菜单方式的全屏幕编辑功能，操作灵活，处理方法简捷，具有良好的人机界面．

The C language is used to achieve the editing and drawing function of ladder graphics for a built-in PMC. The software is structurally compact and has a high reliability, With a dou-bly linked list data structure to describe and record different information for the laddergraphics,the full-screen edit function in the form of a Chinese menu is realized. It is flexiblein operation,easy in processing and with a good man-machine interface.