一个c#代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace experment5_1
{
    class Program
    {
        //Student类包含学生的所有必要信息
        //以及关于这些信息的计算方法，以及输出学生信息的方法
        class Student
        {
            public string stuNumber;    //学号
            public string stuName;  //姓名
            public int[] scores;   //分数
            public int[] scorePoint; //分数对应的点数
            public Course[] courses;   //参加的课程
            public double staGPA;   //标准GPA
            public double ordGPA;   //一般GPA
            public Student() { }
            public Student(string name, string number)  //构造函数重载
            {
                stuName = name;
                stuNumber = number;
            }
            public void setScore(int[] score)   //设置学生的分数
            {
                scores = new int[score.Length]; //实例化scores数组
                for (int i = 0; i < score.Length; i++)
                    scores[i] = score[i];
            }
            public void setPoint()  //设置学分点数
            {
                scorePoint = new int[scores.Length];    //实例化scorepoint数组
                for (int i = 0; i < scores.Length; i++)
                    if (scores[i] >= 90)
                        scorePoint[i] = 4;
                    else if (scores[i] >= 80)
                        scorePoint[i] = 3;
                    else if (scores[i] >= 70)
                        scorePoint[i] = 2;
                    else if (scores[i] >= 60)
                        scorePoint[i] = 1;
                    else
                        scorePoint[i] = 0;
            }
            public void setCourse(Course[] course)  //设置学生参加的课程
            {
                courses = new Course[course.Length];    //实例化courses数组
                for (int i = 0; i < course.Length; i++)
                    courses[i] = course[i];
            }
            public void calGPA()    //计算标准GPA和常见GPA
            {
                //此函数中要使用scorePoint，所以在使用前要先调用setPoint()函数
                //否则会提示未将对象引用实例化
                setPoint();
                int sumSta = 0;
                int sumOrd = 0;
                int sumCre = 0;
                for (int i = 0; i < scores.Length; i++)
                {
                    sumSta += courses[i].couCredit * scorePoint[i];
                    sumOrd += scores[i] * courses[i].couCredit;
                    sumCre += courses[i].couCredit;
                }
                ordGPA = sumSta * 1.0 / sumCre;
                staGPA = sumOrd * 4.0 / (sumCre * 100);
            }
            public void disStudent()
            {
                //要先调用calGPA()来计算GPA
                calGPA();
                Console.WriteLine("学号：{0}\t姓名：{1}", stuNumber, stuName);
                Console.WriteLine("\t课程名\t学分\t分数");
                for (int i = 0; i < courses.Length; i++)
                    Console.WriteLine("\t{0}\t{1}\t{2}", courses[i].couName, courses[i].couCredit, scores[i]);
                Console.WriteLine("常见算法GPA={0:n}，标准算法GPA={1:n}", ordGPA, staGPA);
            }
        }
        //Course类包含课程名称和对应的学分
        class Course
        {
            public string couName;
            public int couCredit;
            public Course() { }
            public Course(string name, int credit)
            {
                couCredit = credit;
                couName = name;
            }
        }
        static void Main(string[] args)
        {
            Student student = new Student("王华", "1");
            Course[] courses = new Course[] { new Course("课程1", 4), new Course("课程2", 3), new Course("课程3", 2), new Course("课程4", 6), new Course("课程5", 3) };
            int[] scores = new int[] { 92, 80, 98, 70, 89 };
            student.setScore(scores);
            student.setCourse(courses);
            student.disStudent();
        }
    }
}

注意对象引用使用前要进行实例化