一、foreach運算元組

int[] i = new int[] { 1, 2, 3, 4, 5,67, 8 };
            foreach(int i1 in i)
            {
                MessageBox.Show(i1.ToString());
            }

二、foreach操作集合

List<int> ints = new List<int>(){1,2,3,4,5,6,7};
           /* ints.Add(1);
            ints.Add(2);
            ints.Add(
 
3);
            ints.Add(4);
            ints.Add(5); */
            foreach(int item in ints)
            {
                MessageBox.Show(item.ToString());
            }

三、foreach操作字典

Dictionary<string, string> dictionary = new Dictionary<string, string>() 
            { 
                { 
 
"AA", "aa" }, 
                { "BB", "bb" } 
            };
            foreach(KeyValuePair<string,string> item in dictionary)

{ string key = item.Key; string value = item.Value; MessageBox.Show(key+"-"+value); }

四、foreach操作自定義List

//實體類
namespace List
{
   public class Person
    {
        
 
public string Name { get; set; }
        public string Sex { get; set; }
        public int Age { get; set; }
        public int Height { get; set; }
        public List<Person> GetUserList() //封裝一個方法得到person的list集合
        {
            List<Person> List = new List<Person>();
            List.Add(new Person
            {
                Name="B",
                Sex="男",
                Age = 18,
                Height=167,

            });
            List.Add(new Person
            {
                Name = "A",
                Sex = "女",
                Age = 19,
                Height = 160,

            });
            return List;

        }
    }
   
}

 //實現
Person person = new Person();
            List<Person> person1 = person.GetUserList();
            foreach (Person item in person1)
            {
                MessageBox.Show(item.Name+item.Sex+item.Age+item.Height);
            } Person person = new Person();
            List<Person> person1 = person.GetUserList();
            foreach (Person item in person1)
            {
                MessageBox.Show(item.Name+item.Sex+item.Age+item.Height);
            }