C# 判断list类型中某字段是否存在相同值

新建model

public class Student
{

    public int ID { get; set; }

    public string Name { get; set; }

    public string  Class  {get; set; }  

}

新建list

List<Student> stu = new List<Student>();

判断name是否重复 /////// 判断name与class是否都重复

bool isRepeat = stu.GroupBy(i => i.Name).Any(g => g.Count() > 1);

bool isRepeat = stu.GroupBy(i => new { m.Name, m.Class}).Any(g => g.Count() > 1);

isRepeat 为true 存在重复，false 不存在