c# - 使用迭代方法和 LINQ 查找模型的最常见属性

Question

我有以下模型类:

public class Student
{
     public string Name { get; set; }
     public string Major { get; set; }
     public int Age { get; set; }
}


public string GetPrimaryMajor(List<Student> students)
{ 
     ... 
}

如何使用迭代和 LINQ 方法实现方法 GetPrimaryMajor() 以确定 students 参数中最常出现的 Major？

Answer 1

因为这显然是家庭作业，所以我会给你一个简单的/更容易的，你可以从那里找出迭代​​方法。

public string GetPrimaryMajor(List<Student> students)
{    
    var mostCommonMajor = students
                              .GroupBy(m => m.Major)
                              .OrderByDescending(gp => gp.Count())
                              .FirstOrDefault()? // null-conditional operator
                              .Select(s => s.Major)
                              .FirstOrDefault();

    return mostCommonMajor;
}

对于迭代方法，将以下伪代码视为一种潜在的简单迭代(性能可能较差)算法:

// Iterate students
// Track count of each major
// Keep track of most commonly occurring major by comparing count of 
// currently iterated value vs current most commonly occurring value count
// Return most commonly occurred major at end of loop.