Skip to content

CSharp_冯翌航_未央-工物31 #17

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 1 commit into
base: main
Choose a base branch
from
Open

CSharp_冯翌航_未央-工物31 #17

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
198 changes: 139 additions & 59 deletions Homework/Program.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,4 +1,4 @@
// See https://aka.ms/new-console-template for more information
// See https://aka.ms/new-console-template for more information
using System;
using System.Collections.Generic;
using System.IO;
Expand All @@ -9,43 +9,51 @@ namespace StudentManagementSystem
public enum Grade
{
// TODO: 定义成绩等级 F(0), D(60), C(70), B(80), A(90)

F = 0,
D = 60,
C = 70,
B = 80,
A = 90,
}

// 泛型仓储接口
public interface IRepository<T>
{
// TODO: 定义接口方法
// Add(T item)
// Remove(T item) 返回bool
// GetAll() 返回List<T>
// Find(Func<T, bool> predicate) 返回List<T>
public void Add(T item);
public bool Remove(T item);
public List<T> GetAll();
List<T> Find(Func<T, bool> predicate);

}

// 学生类
public class Student : IComparable<Student>
{
// TODO: 定义字段 StudentId, Name, Age


public readonly string StudentId;
public readonly string Name;
public readonly int Age;

public Student(string studentId, string name, int age)
{
// TODO: 实现构造方法，包含参数验证（空值检查）

if ((studentId is null) || (name is null))
{
throw new ArgumentException("Null Parameter");
}
StudentId = studentId;
Name = name;
Age = age;
}

public override string ToString()
{
// TODO: 返回格式化的学生信息字符串

return $$"""Student { StudentId : {{StudentId}}, Name : {{Name}}, Age : {{Age}} }""";
}

// TODO: 实现IComparable接口，按学号排序
// 提示：使用string.Compare方法
public int CompareTo(Student? other)
{

return String.Compare(StudentId, other?.StudentId);
}

public override bool Equals(object? obj)
Expand All @@ -62,19 +70,22 @@ public override int GetHashCode()
// 成绩类
public class Score
{
// TODO: 定义字段 Subject, Points

public readonly string Subject;
public readonly double Points;

public Score(string subject, double points)
{
// TODO: 实现构造方法，包含参数验证

if (subject is null)
{
throw new ArgumentException("Null Parameter");
}
Subject = subject;
Points = points;
}

public override string ToString()
{
// TODO: 返回格式化的成绩信息

return $$"""Score { Subject : {{Subject}}, Points : {{Points}} }""";
}
}

Expand All @@ -83,39 +94,43 @@ public class StudentManager : IRepository<Student>
{
// TODO: 定义私有字段存储学生列表
// 提示：使用List<Student>存储

private List<Student> Students = new List<Student>();

public void Add(Student item)
{
// TODO: 实现添加学生的逻辑
// 1. 参数验证
// 2. 添加到列表

if (item is not null)
{
Students.Add(item);
}
}

public bool Remove(Student item)
{
// TODO: 实现Remove方法

return Students.Remove(item);
}

public List<Student> GetAll()
{
// TODO: 返回学生列表的副本

return new List<Student>(Students);
}

public List<Student> Find(Func<Student, bool> predicate)
{
// TODO: 使用foreach循环查找符合条件的学生

var res = new List<Student>();
foreach (var item in Students)
{
if (predicate(item))
{
res.Add(item);
}
}
return res;
}

// 查找年龄在指定范围内的学生
public List<Student> GetStudentsByAge(int minAge, int maxAge)
{
// TODO: 使用foreach循环和if判断实现年龄范围查询

return this.Find(student => student.Age <= maxAge && student.Age >= minAge);
}
}

Expand All @@ -124,46 +139,63 @@ public class ScoreManager
{
// TODO: 定义私有字段存储成绩字典
// 提示：使用Dictionary<string, List<Score>>存储

private Dictionary<string, List<Score>> ScoreDict = new Dictionary<string, List<Score>>();

public void AddScore(string studentId, Score score)
{
// TODO: 实现添加成绩的逻辑
// 1. 参数验证
// 2. 初始化学生成绩列表（如不存在）
// 3. 添加成绩

if (studentId is not null)
{
if (! ScoreDict.ContainsKey(studentId))
{
ScoreDict.Add(studentId, new List<Score>());
}
ScoreDict[studentId].Add(score);
}
}

public List<Score> GetStudentScores(string studentId)
{
// TODO: 获取指定学生的所有成绩

return ScoreDict[studentId];
}

public double CalculateAverage(string studentId)
{
// TODO: 计算指定学生的平均分
// 提示：使用foreach循环计算总分，然后除以科目数

double res = 0;
var l = ScoreDict[studentId];
foreach (var score in l)
{
res += score.Points;
}
return res / l.Count();
}

// TODO: 使用模式匹配实现成绩等级转换
public Grade GetGrade(double score)
{

return score switch
{
< 60 => Grade.F,
>= 60 and < 70 => Grade.D,
>= 70 and < 80 => Grade.C,
>= 80 and < 90 => Grade.B,
>= 90 => Grade.A,
_ => throw new ArgumentOutOfRangeException("Invalid score value")
};
}

public List<(string StudentId, double Average)> GetTopStudents(int count)
{
// TODO: 使用简单循环获取平均分最高的学生
// 提示：可以先计算所有学生的平均分，然后排序取前count个

var res = new List<(string StudentId, double Average)>();
foreach (var item in ScoreDict)
{
res.Add((item.Key, CalculateAverage(item.Key)));
}
res.Sort((x, y) => -x.Item2.CompareTo(y.Item2));
return res.GetRange(0, count);
}

public Dictionary<string, List<Score>> GetAllScores()
{
return new Dictionary<string, List<Score>>(scores);
return new Dictionary<string, List<Score>>(ScoreDict);
}
}

Expand All @@ -177,7 +209,14 @@ public void SaveStudentsToFile(List<Student> students, string filePath)
try
{
// 在这里实现文件写入逻辑

using (StreamWriter writer = new StreamWriter(filePath))
{
writer.WriteLine("StudentId,Name,Age");
foreach (var student in students)
{
writer.WriteLine($"{student.StudentId},{student.Name},{student.Age}");
}
}
}
catch (Exception ex)
{
Expand All @@ -193,8 +232,24 @@ public List<Student> LoadStudentsFromFile(string filePath)
// 提示：使用StreamReader，解析CSV格式
try
{
// 在这里实现文件读取逻辑

using (StreamReader reader = new StreamReader(filePath))
{
string line;
// 跳过标题行
reader.ReadLine();

while ((line = reader.ReadLine()) != null)
{
var parts = line.Split(',');
if (parts.Length == 3)
{
string studentId = parts[0].Trim();
string name = parts[1].Trim();
int age = int.Parse(parts[2].Trim());
students.Add(new Student(studentId, name, age));
}
}
}
}
catch (Exception ex)
{
Expand Down Expand Up @@ -241,21 +296,46 @@ static void Main(string[] args)
// 3. 测试年龄范围查询
Console.WriteLine("\n3. 查找年龄在19-20岁的学生:");
// TODO: 调用GetStudentsByAge方法并显示结果

var students_temp = studentManager.GetStudentsByAge(19, 20);
foreach (var student in students_temp)
{
Console.WriteLine(student);
}

// 4. 显示学生成绩统计
Console.WriteLine("\n4. 学生成绩统计:");
// TODO: 遍历所有学生，显示其成绩、平均分和等级
foreach (var student in studentManager.GetAll())
{
var scores = scoreManager.GetStudentScores(student.StudentId);
Console.WriteLine($"{student.Name} 的成绩:");
foreach (var score in scores)
{
Console.WriteLine($"科目: {score.Subject}, 分数: {score.Points}, 等级: {scoreManager.GetGrade(score.Points)}");
}
double average = scoreManager.CalculateAverage(student.StudentId);
Console.WriteLine($"平均分: {average}, 等级: {scoreManager.GetGrade(average)}\n");
}


// 5. 显示排名（简化版）
Console.WriteLine("\n5. 平均分最高的学生:");
// TODO: 调用GetTopStudents(1)方法显示第一名
Console.WriteLine(scoreManager.GetTopStudents(1)[0].StudentId);


// 6. 文件操作
Console.WriteLine("\n6. 数据持久化演示:");
// TODO: 保存和读取学生文件
string filePath = "students.csv";
// 保存学生数据到文件
dataManager.SaveStudentsToFile(studentManager.GetAll(), filePath);
Console.WriteLine($"学生数据已保存到 {filePath}");

// 从文件加载学生数据
var loadedStudents = dataManager.LoadStudentsFromFile(filePath);
Console.WriteLine("从文件加载的学生数据:");
foreach (var student in loadedStudents)
{
Console.WriteLine(student);
}


}
Expand All @@ -268,4 +348,4 @@ static void Main(string[] args)
Console.ReadKey();
}
}
}
}