C#常用集合的使用(转载)
2019-03-07 17:24 会飞的雪鹿 阅读(579) 评论(0) 编辑 收藏 举报大多数集合都在System.Collections,System.Collections.Generic两个命名空间。其中System.Collections.Generic专门用于泛型集合。 针对特定类型的集合类型位于System.Collections.Specialized;命名空间; 线程安全的集合类位于System.Collections.Concurrent;命名空间。 下面是集合和列表实现的接口如下: 一、列表 [Serializable] [DebuggerTypeProxy(typeof(Mscorlib_CollectionDebugView<>))] [DebuggerDisplay("Count = {Count}")] public class List<T> : IList<T>, ICollection<T>, IEnumerable<T>, IList, ICollection, IEnumerable 从这个可以看出,泛型集合List<T>实现了这么多接口,具体接口的信息可以通过工具查看。 using System; using System.Collections.Generic; namespace ConsoleApplication1 { public class Program { static void Main(string[] args) { List<String> list = new List<string>(); list.Add("张三"); list.Add("李四"); list.Add("王五"); list.Add("田六"); list.Add("赵七"); for (int i = 0; i < list.Count; i++) { Console.WriteLine("for循环:" + i.ToString() + "=" + list[i]); } list.RemoveAt(0); foreach (String item in list) { Console.WriteLine("foreach迭代:" + item); } list.AddRange(new String[] { "Hello1", "Hello2", "Hello3" }); list.ForEach(Print); Console.Read(); } private static void Print(String item) { Console.WriteLine("ForEach:" + item); } } } 二、队列 队列先进先出,一头进一头出,用Queue<T>实现 [Serializable] [DebuggerTypeProxy(typeof(System_QueueDebugView<>))] [ComVisible(false)] [DebuggerDisplay("Count = {Count}")] public class Queue<T> : IEnumerable<T>, ICollection, IEnumerable 可以看出队列实现了集合的接口,迭代的接口 using System; using System.Collections.Generic; namespace ConsoleApplication1 { public class Program { static void Main(string[] args) { Queue<String> queue = new Queue<string>(); //进队 queue.Enqueue("张三"); queue.Enqueue("李四"); queue.Enqueue("王五"); queue.Enqueue("田六"); queue.Enqueue("赵七"); foreach (String item in queue) { Console.WriteLine("foreach迭代:" + item); } //出队 while (queue.Count > 0) { Console.WriteLine("出队:" + queue.Dequeue()); } Console.Read(); } } } 三、栈 栈:从同一边先进后出,用Stack<T>实现 [DebuggerDisplay("Count = {Count}")] [DebuggerTypeProxy(typeof(System_StackDebugView<>))] [ComVisible(false)] public class Stack<T> : IEnumerable<T>, ICollection, IEnumerable 栈也是实现了集合接口与迭代接口的 using System; using System.Collections.Generic; namespace ConsoleApplication1 { public class Program { static void Main(string[] args) { Stack<String> stack = new Stack<string>(); //进栈 stack.Push("张三"); stack.Push("李四"); stack.Push("王五"); stack.Push("田六"); stack.Push("赵七"); foreach (String item in stack) { Console.WriteLine("foreach迭代:" + item); } //出栈 while (stack.Count > 0) { Console.WriteLine("出栈:" + stack.Pop()); } Console.Read(); } } } 四、链表 LinkedList是一个双向链表,链表有个有点,就是在链表中间插入、删除元素很快,但是查找中间与末尾的元素很慢,需要一个节点一个节点的去找。 [Serializable] [DebuggerTypeProxy(typeof(System_CollectionDebugView<>))] [DebuggerDisplay("Count = {Count}")] [ComVisible(false)] public class LinkedList<T> : ICollection<T>, IEnumerable<T>, ICollection, IEnumerable, ISerializable, IDeserializationCallback 由此可见链表也是有集合的特性的,可以迭代,同时还有链表的特性 using System; using System.Collections.Generic; namespace ConsoleApplication1 { public class Program { static void Main(string[] args) { LinkedList<String> lList = new LinkedList<string>(); LinkedListNode<String> node = new LinkedListNode<string>("root"); lList.AddFirst(node); node = lList.AddAfter(node, "张三"); node = lList.AddAfter(node, "李四"); node = lList.AddAfter(node, "王五"); node = lList.AddAfter(node, "田六"); node = lList.AddAfter(node, "赵七"); foreach (String item in lList) { Console.WriteLine("foreach迭代:" + item); } node = lList.First; Console.WriteLine("第一个元素:" + node.Value); node = lList.Last; Console.WriteLine("最后一个元素:" + node.Value); Console.Read(); } } } 五、有序列表 SortedList采用键-值对存储,键不能重复,并且会根据key进行排序 [Serializable] [DebuggerTypeProxy(typeof(System_DictionaryDebugView<,>))] [DebuggerDisplay("Count = {Count}")] [ComVisible(false)] public class SortedList<TKey, TValue> : IDictionary<TKey, TValue>, ICollection<KeyValuePair<TKey, TValue>>, IEnumerable<KeyValuePair<TKey, TValue>>, IDictionary, ICollection, IEnumerable 可以看出SortedList不仅具有字典的特性,还有集合,迭代的功能 using System; using System.Collections.Generic; namespace ConsoleApplication1 { public class Program { static void Main(string[] args) { //Key必须唯一,如果不唯一可以考虑Lookup<TKey,TElement> SortedList<int, String> sList = new SortedList<int, string>(); sList.Add(100, "张三"); sList.Add(21, "李四"); sList.Add(13, "王五"); sList.Add(44, "田六"); sList.Add(35, "赵七"); foreach (KeyValuePair<int, String> item in sList) { Console.WriteLine("key=" + item.Key.ToString() + ";value=" + item.Value); } Console.Read(); } } } 六、字典 字典是很复杂的数据结构,允许通过key来查找值,字典可以自由添加、删除元素,没有集合由于移动元素导致的开销。 [Serializable] [DebuggerTypeProxy(typeof(Mscorlib_DictionaryDebugView<,>))] [DebuggerDisplay("Count = {Count}")] [ComVisible(false)] public class Dictionary<TKey, TValue> : IDictionary<TKey, TValue>, ICollection<KeyValuePair<TKey, TValue>>, IEnumerable<KeyValuePair<TKey, TValue>>, IDictionary, ICollection, IEnumerable, ISerializable, IDeserializationCallback 可以看出字典也具有集合的特性,可以迭代 using System; using System.Collections.Generic; namespace ConsoleApplication1 { public class Program { static void Main(string[] args) { //Key必须唯一 Dictionary<int, String> dict = new Dictionary<int, string>(); dict.Add(11, "张三"); dict.Add(1, "李四"); dict.Add(2, "王五"); dict.Add(16, "田六"); dict.Add(12, "赵七"); foreach (KeyValuePair<int, String> item in dict) { Console.WriteLine("key=" + item.Key.ToString() + ";value=" + item.Value); } Console.Read(); } } } 说到字典,顺便谈一下有序字典,与有序列表对应;SortedDictionary,SortedList,SortedSet 会根据Key进行排序 using System; using System.Collections.Generic; namespace ConsoleApplication1 { public class Program { static void Main(string[] args) { //Key必须唯一 SortedDictionary<int, String> dict = new SortedDictionary<int, string>(); dict.Add(11, "张三"); dict.Add(1, "李四"); dict.Add(2, "王五"); dict.Add(16, "田六"); dict.Add(12, "赵七"); foreach (KeyValuePair<int, String> item in dict) { Console.WriteLine("key=" + item.Key.ToString() + ";value=" + item.Value); } Console.Read(); } } } 七、集 集(Set):包含不重复元素,常用HashSet,SortedSet [Serializable] [DebuggerDisplay("Count = {Count}")] [DebuggerTypeProxy(typeof(HashSetDebugView<>))] public class HashSet<T> : ISerializable, IDeserializationCallback, ISet<T>, ICollection<T>, IEnumerable<T>, IEnumerable [Serializable] [DebuggerTypeProxy(typeof(SortedSetDebugView<>))] [DebuggerDisplay("Count = {Count}")] public class SortedSet<T> : ISet<T>, ICollection<T>, IEnumerable<T>, ICollection, IEnumerable, ISerializable, IDeserializationCallback using System; using System.Collections.Generic; namespace ConsoleApplication1 { public class Program { static void Main(string[] args) { HashSet<String> hSet = new HashSet<string>(); hSet.Add("张三"); hSet.Add("李四"); hSet.Add("王五"); hSet.Add("田六"); hSet.Add("赵七"); foreach (String item in hSet) { Console.WriteLine("foreach迭代:" + item); } Console.Read(); } } } using System; using System.Collections.Generic; namespace ConsoleApplication1 { public class Program { static void Main(string[] args) { SortedSet<String> hSet = new SortedSet<string>(); hSet.Add("张三"); hSet.Add("李四"); hSet.Add("王五"); hSet.Add("田六"); hSet.Add("赵七"); foreach (String item in hSet) { Console.WriteLine("foreach迭代:" + item); } Console.Read(); } } }