C# List, Array, Dictionary相互转换

Posted 2021-10-28 luckyzli

• 将Array转换为List
• 将List转换为Array
• 将Array转换为Dictionary
• 将Dictionary 转换为Array
• 将List转换为Dictionary
• 将Dictionary转换为List
  首先，我们定义一个“Student”类，它有三个自动实现属性。

    class Student
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public string Gender { get; set; }
    }        

1. Array转换为List

将数组转换成一个List，我先创建了一个student类型的数组。

        static void Main(string[] args)
        {
            Student[] studentArray = new Student[3];
            studentArray[0] = new Student()
            {
                Id = 12,
                Name = "Lucky",
                Gender = "Male"
            };
            studentArray[1] = new Student()
            {
                Id = 23,
                Name = "Poppy",
                Gender = "Male"
            };
            studentArray[2] = new Student()
            {
                Id = 55,
                Name = "Jack",
                Gender = "Female"
            };
            //foreach循环数组
            foreach (Student student in studentArray)
            {
                Console.WriteLine("Id = " + student.Id + " " + " Name = " + student.Name + "  " + " Gender = " + student.Gender);
            }                

            //1. 数组转成List
            List<Student> StudentList = studentArray.ToList<Student>();
            foreach (Student student in StudentList)
            {
                Console.WriteLine("Id = " + student.Id + " " + " Name = " + student.Name + " " + " Gender = " + student.Gender);
            }

2. List转换为Array

            Student[] ListToArray = StudentList.ToArray<Student>();
            foreach (Student student in ListToArray)
            {
                Console.WriteLine("Id = " + student.Id + " " + " Name = " + student.Name + " " + " Gender = " + student.Gender);
            }

3. Array转Dictionary

            Dictionary<int, Student> StudentDictionary = studentArray.ToDictionary(key=>key.Id, Studentobj => Studentobj);
            foreach (KeyValuePair<int, Student> student in StudentDictionary)
            {
                Console.WriteLine("Id = " + student.Key + " " + " Name = " + student.Value.Name + " " + " Gender = " + student.Value.Gender);
            }

4. Dictionary转Array

            Student[] DictionaryToArray = StudentDictionary.Values.ToArray();
            foreach (Student student in DictionaryToArray)
            {
                Console.WriteLine("Id = " + student.Id + " " + " Name = " + student.Name + " " + " Gender = " + student.Gender);
            }

5. List转Dictionary

            Dictionary<int, Student> ListToDictionary = ListToArray.ToDictionary(key => key.Id, value => value);
            foreach (KeyValuePair<int, Student> student in ListToDictionary)
            {
                Console.WriteLine("Id = " + student.Key + " " + " Name = " + student.Value.Name + " " + " Gender = " + student.Value.Gender);
            }

6. Dictionary转List

            List<Student> DictionaryToList = StudentDictionary.Values.ToList();
            foreach (Student student in DictionaryToList)
            {
                Console.WriteLine("Id = " + student.Id + " " + " Name = " + student.Name + " " + " Gender = " + student.Gender);
            }