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คุณสมบัติ Dictionary.Keys ใน C #


คุณสมบัติ Dictionary.Keys ใน C # ใช้เพื่อดึงคีย์ทั้งหมดในพจนานุกรม

ไวยากรณ์

ต่อไปนี้เป็นไวยากรณ์ -

public System.Collections.Generic.Dictionary<TKey, TValue>.KeyCollection Keys { get; }

ตัวอย่าง

ให้เราดูตัวอย่างการใช้งานคุณสมบัติ Dictionary.Keys -

using System;
using System.Collections.Generic;
public class Demo {
   public static void Main(){
      Dictionary<string, string> dict =
      new Dictionary<string, string>();
      dict.Add("One", "Kagido");
      dict.Add("Two", "Ngidi");
      dict.Add("Three", "Devillers");
      dict.Add("Four", "Smith");
      dict.Add("Five", "Warner");
      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);
      }
      Console.Write("\nAll the keys..\n");
      Dictionary<string, string>.KeyCollection allKeys =
      dict.Keys;
      foreach(string str in allKeys){
         Console.WriteLine("Key = {0}", str);
      }
   }
}

ผลลัพธ์

สิ่งนี้จะสร้างผลลัพธ์ต่อไปนี้ -

Count of elements = 5
Key/value pairs...
Key = One, Value = Kagido
Key = Two, Value = Ngidi
Key = Three, Value = Devillers
Key = Four, Value = Smith
Key = Five, Value = Warner
All the keys..
Key = One
Key = Two
Key = Three
Key = Four
Key = Five

ตัวอย่าง

ให้เราดูตัวอย่างอื่นเพื่อใช้คุณสมบัติ Dictionary.Keys -

using System;
using System.Collections.Generic;
public class Demo {
   public static void Main(){
      Dictionary<string, string> dict =
      new Dictionary<string, string>();
      dict.Add("One", "Chris");
      dict.Add("Two", "Steve");
      dict.Add("Three", "Messi");
      dict.Add("Four", "Ryan");
      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);
      }
      Console.WriteLine("Value for key three = "+dict["Three"]);
      dict["Three"] = "Katie";
      Console.WriteLine("Updated value associated with key Three...");
      Console.WriteLine(dict["Three"]);
      Console.Write("\nAll the keys..\n");
      Dictionary<string, string>.KeyCollection allKeys = dict.Keys;
      foreach(string str in allKeys){
         Console.WriteLine("Key = {0}", str);
      }
   }
}

ผลลัพธ์

สิ่งนี้จะสร้างผลลัพธ์ต่อไปนี้ -

Count of elements = 5
Key/value pairs...
Key = One, Value = Chris
Key = Two, Value = Steve
Key = Three, Value = Messi
Key = Four, Value = Ryan
Key = Five, Value = Nathan
Value for key three = Messi
Updated value associated with key Three...
Katie
All the keys..
Key = One
Key = Two
Key = Three
Key = Four
Key = Five