C#的编写的学生成绩统计管理系统源代码： 符合要求：成绩修改，添加，删除。成绩的总分，平均分，排序。各成绩档比例-C# prepared by the students scores source code management system : compliance with the requirements : results change, add, delete. The combined results, the aver

C#的编写的学生成绩统计管理系统源代码： 符合要求：成绩修改，添加，删除。成绩的总分，平均分，排序。各成绩档比例-C# prepared by the students scores source code management system : compliance with the requirements : results change, add, delete. The combined results, the aver