C#中的Dictionary.Clear方法
C#中的Dictionary.Clear()方法从Dictionary<TKey,TValue>中删除所有键/值对。
语法
public void Clear();
现在让我们看一个实现Dictionary.Clear()方法的示例-
示例
using System;
using System.Collections.Generic;
public class Demo {
   public static void Main(){
      Dictionary<string, string> dict =
      new Dictionary<string, string>();
      dict.Add("One", "John");
      dict.Add("Two", "Tom");
      dict.Add("Three", "Jacob");
      dict.Add("Four", "Kevin");
      dict.Add("Five", "Nathan");
      Console.WriteLine("Count of elements = "+dict.Count);
      Console.WriteLine("\nKey/value pairs...");
      foreach(KeyValuePair<string, string> res in dict){
         Console.WriteLine("Key = {0}, Value = {1}", res.Key, res.Value);
      }
      dict.Clear();
      Console.WriteLine("Cleared Key/value pairs...");
      foreach(KeyValuePair<string, string> res in dict){
         Console.WriteLine("Key = {0}, Value = {1}", res.Key, res.Value);
      }
      Console.WriteLine("Count of elements now = "+dict.Count);
   }
}输出结果
这将产生以下输出-
Count of elements = 5 Key/value pairs... Key = One, Value = John Key = Two, Value = Tom Key = Three, Value = Jacob Key = Four, Value = Kevin Key = Five, Value = Nathan Cleared Key/value pairs... Count of elements now = 0
现在让我们来看另一个实现Dictionary.Clear()方法的示例-
示例
using System;
using System.Collections.Generic;
public class Demo {
   public static void Main(){
      Dictionary<string, string> dict =
      new Dictionary<string, string>();
      dict.Add("One", "John");
      dict.Add("Two", "Tom");
      dict.Add("Three", "Jacob");
      dict.Add("Four", "Kevin");
      dict.Add("Five", "Nathan");
      Console.WriteLine("Count of elements = "+dict.Count);
      dict.Add("Six", "Anne");
      dict.Add("Seven", "Katoe");
      Console.WriteLine("Count of elements (updated) = "+dict.Count);
      Console.WriteLine("Key/value pairs...");
      foreach(KeyValuePair<string, string> res in dict){
         Console.WriteLine("Key = {0}, Value = {1}", res.Key, res.Value);
      }
      dict.Clear();
      Console.WriteLine("Cleared Key/value pairs...");
      foreach(KeyValuePair<string, string> res in dict){
         Console.WriteLine("Key = {0}, Value = {1}", res.Key, res.Value);
      }
   }
}输出结果
这将产生以下输出-
Count of elements = 5 Count of elements (updated) = 7 Key/value pairs... Key = One, Value = John Key = Two, Value = Tom Key = Three, Value = Jacob Key = Four, Value = Kevin Key = Five, Value = Nathan Key = Six, Value = Anne Key = Seven, Value = Katoe Cleared Key/value pairs...
