要获取ListDictionary中包含的键/值对的数量,代码如下-
using System;
using System.Collections;
using System.Collections.Specialized;
public class Demo {
   public static void Main(){
      ListDictionary dict1 = new ListDictionary();
      dict1.Add("A", "Books");
      dict1.Add("B", "Electronics");
      dict1.Add("C", "Smart Wearables");
      dict1.Add("D", "Pet Supplies");
      dict1.Add("E", "Clothing");
      dict1.Add("F", "Footwear");
      Console.WriteLine("ListDictionary1 elements...");
      foreach(DictionaryEntry d in dict1){
         Console.WriteLine(d.Key + " " + d.Value);
      }
      ListDictionary dict2 = new ListDictionary();
      dict2.Add("1", "One");
      dict2.Add("2", "Two");
      dict2.Add("3", "Three");
      dict2.Add("4", "Four");
      dict2.Add("5", "Five");
      dict2.Add("6", "Six");
      Console.WriteLine("\nListDictionary2 elements...");
      foreach(DictionaryEntry d in dict2){
         Console.WriteLine(d.Key + " " + d.Value);
      }
      Console.WriteLine("Count of key/value pairs in Dictionary 2 = "+dict2.Count);
      ListDictionary dict3 = new ListDictionary();
      dict3 = dict2;
      Console.WriteLine("\nIs ListDictionary3 equal to ListDictionary2? = "+(dict3.Equals(dict2)));
      dict3.Clear();
      Console.WriteLine("Count of key/value pairs in Dictionary 3 = "+dict3.Count);
   }
}输出结果
这将产生以下输出-
ListDictionary1 elements... A Books B Electronics C Smart Wearables D Pet Supplies E Clothing F Footwear ListDictionary2 elements... 1 One 2 Two 3 Three 4 Four 5 Five 6 Six Count of key/value pairs in Dictionary 2 = 6 Is ListDictionary3 equal to ListDictionary2? = True Count of key/value pairs in Dictionary 3 = 0
让我们看另一个例子-
using System;
using System.Collections;
using System.Collections.Specialized;
public class Demo {
   public static void Main(){
      ListDictionary dict1 = new ListDictionary();
      dict1.Add("A", "Books");
      dict1.Add("B", "Electronics");
      dict1.Add("C", "Smart Wearables");
      dict1.Add("D", "Pet Supplies");
      dict1.Add("E", "Clothing");
      Console.WriteLine("ListDictionary1 elements...");
      foreach(DictionaryEntry d in dict1){
         Console.WriteLine(d.Key + " " + d.Value);
      }
      Console.WriteLine("Count of key/value pairs in Dictionary1 = "+dict1.Count);
      ListDictionary dict2 = new ListDictionary();
      dict2.Add("1", "One");
      dict2.Add("2", "Two");
      dict2.Add("3", "Three");
      dict2.Add("4", "Four");
      dict2.Add("5", "Five");
      dict2.Add("6", "Six");
      Console.WriteLine("\nListDictionary2 key-value pairs...");
      IDictionaryEnumerator demoEnum = dict2.GetEnumerator();
      while (demoEnum.MoveNext())
         Console.WriteLine("Key = " + demoEnum.Key + ", Value = "+ demoEnum.Value);
      Console.WriteLine("Count of key/value pairs in Dictionary2 = "+dict2.Count);
   }
}输出结果
这将产生以下输出-
ListDictionary1 elements... A Books B Electronics C Smart Wearables D Pet Supplies E Clothing Count of key/value pairs in Dictionary1 = 5 ListDictionary2 key-value pairs... Key = 1, Value = One Key = 2, Value = Two Key = 3, Value = Three Key = 4, Value = Four Key = 5, Value = Five Key = 6, Value = Six Count of key/value pairs in Dictionary2 = 6