C#的6种常用集合类大比拼

ArrayList类

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;
namespace ConsoleApplication1
... {
    class Program
    ...{
        static void Main(string[] args)
        ...{
             ArrayList al = new ArrayList();
             al.Add(100);//单个添加
            foreach (int number in new int[6] ...{ 9, 3, 7, 2, 4, 8 })
            ...{
                 al.Add(number);//集体添加方法一//清清月儿 http://blog.youkuaiyun.com/21aspnet/
             }
            int[] number2 = new int[2] ...{ 11,12 };
             al.AddRange(number2);//集体添加方法二
             al.Remove(3);//移除值为3的
             al.RemoveAt(3);//移除第3个
             ArrayList al2 = new ArrayList(al.GetRange(1, 3));//新ArrayList只取旧ArrayList一部份


             Console.WriteLine("遍历方法一:");
            foreach (int i in al)//不要强制转换
            ...{
                 Console.WriteLine(i);//遍历方法一
             }

             Console.WriteLine("遍历方法二:");
            for (int i = 0; i != al2.Count; i++)//数组是length
            ...{
                int number = (int)al2[i];//一定要强制转换
                 Console.WriteLine(number);//遍历方法二

             }
         }
     }
}

 

 

 

 

 

 

 

 

 

 

 

 

2.Stack类

栈，后进先出。push方法入栈，pop方法出栈。

 

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;
namespace ConsoleApplication1
... {
    class Program
    ...{
        static void Main(string[] args)
        ...{
              Stack sk = new Stack();
              Stack sk2 = new Stack();
            foreach (int i in new int[4] ...{ 1, 2, 3, 4 })
            ...{
                  sk.Push(i);//填充
                  sk2.Push(i);
              }
            
            foreach (int i in sk)
            ...{
                  Console.WriteLine(i);//遍历
              }

              sk.Pop();
              Console.WriteLine("Pop");
            foreach (int i in sk)
            ...{
                  Console.WriteLine(i);
              }
            
              sk2.Peek();//弹出最后一项不删除//清清月儿 http://blog.youkuaiyun.com/21aspnet/
              Console.WriteLine("Peek");
            foreach (int i in sk2)
            ...{
                  Console.WriteLine(i);
              }

            while (sk2.Count != 0)
            ...{
                int i = (int)sk2.Pop();//清空
                  sk2.Pop();//清空
              }
              Console.WriteLine("清空");
            foreach (int i in sk2)
            ...{
                  Console.WriteLine(i);
              }
          }
      }
}

 

 

 

 

 

 

 

 

 

3.Queue类

队列，先进先出。enqueue方法入队列，dequeue方法出队列。

 

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;
namespace ConsoleApplication1
... {
    class Program
    ...{
        static void Main(string[] args)
        ...{
              Queue qu = new Queue();
              Queue qu2 = new Queue();
            foreach (int i in new int[4] ...{ 1, 2, 3, 4 })
            ...{
                  qu.Enqueue(i);//填充
                  qu2.Enqueue(i);
              }
            
            foreach (int i in qu)
            ...{
                  Console.WriteLine(i);//遍历
              }

              qu.Dequeue();
              Console.WriteLine("Dequeue");
            foreach (int i in qu)
            ...{
                  Console.WriteLine(i);
              }
            
              qu2.Peek();//弹出最后一项不删除
              Console.WriteLine("Peek");
            foreach (int i in qu2)
            ...{
                  Console.WriteLine(i);
              }

            while (qu2.Count != 0)
            ...{
                int i = (int)qu2.Dequeue();//清空
                  qu2.Dequeue();//清空
              }
              Console.WriteLine("清空");
            foreach (int i in qu2)
            ...{
                  Console.WriteLine(i);
              }
          }
      }
}

 

 

 

 

 

 

4.Hashtable类

哈希表，名-值对。类似于字典(比数组更强大)。哈希表是经过优化的，访问下标的对象先散列过。如果以任意类型键值访问其中元素会快于其他集合。GetHashCode()方法返回一个int型数据，使用这个键的值生成该int型数据。哈希表获取这个值最后返回一个索引，表示带有给定散列的数据项在字典中存储的位置。

 

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;
namespace ConsoleApplication1
... {
    class Program
    ...{
        public static void Main()
        ...{

            // Creates and initializes a new Hashtable.
              Hashtable myHT = new Hashtable();
              myHT.Add("one", "The");
              myHT.Add("two", "quick");
              myHT.Add("three", "brown");
              myHT.Add("four", "fox");

            // Displays the Hashtable.//清清月儿 http://blog.youkuaiyun.com/21aspnet/
              Console.WriteLine("The Hashtable contains the following:");
              PrintKeysAndValues(myHT);
          }


        public static void PrintKeysAndValues(Hashtable myHT)
        ...{
            foreach (string s in myHT.Keys)
                  Console.WriteLine(s);

              Console.WriteLine(" -KEY- -VALUE-");
            foreach (DictionaryEntry de in myHT)
                  Console.WriteLine(" {0}: {1}", de.Key, de.Value);
              Console.WriteLine();
          }
      }
}

 

 

 

 

 

5.SortedList类

与哈希表类似，区别在于SortedList中的Key数组排好序的。

 

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;
namespace ConsoleApplication1
... {
    class Program
    ...{
        public static void Main()
        ...{

              SortedList sl = new SortedList();
              sl["c"] = 41;
              sl["a"] = 42;
              sl["d"] = 11;
              sl["b"] = 13;

            foreach (DictionaryEntry element in sl)
            ...{
                string s = (string)element.Key;
                int i = (int)element.Value;
                  Console.WriteLine("{0},{1}",s,i);
              }
          }
      }
}