B树的维护、查询及图形仿真 设计与实现B-树存储结构，以及B-树构造、插入、删除、查找等操作，并以图形方式模拟这一动态过程。-The maintenance of the B-tree, inquiries and graphic simulation design and realization of a B-tree storage structure, as well as the B-tree structure, insert, delete, search operation, a