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Dictionary.ContainsValue() วิธีใน C #


Dictionary.ContainsValue() ใน C# ใช้เพื่อตรวจสอบว่า Dictionary มีค่าเฉพาะหรือไม่

ไวยากรณ์

public bool ContainsValue (TValue val);

ด้านบน Val คือค่าที่จะค้นหา

ให้เราดูตัวอย่างการใช้เมธอด Dictionary.ContainsValue() -

ตัวอย่าง

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);
      }
      if (dict.ContainsValue("Kevin"))
         Console.WriteLine("Value found!");
      else
         Console.WriteLine("Value isn't in the dictionary!");
      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);
   }
}

ผลลัพธ์

สิ่งนี้จะสร้างผลลัพธ์ต่อไปนี้ -

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
Value found!
Cleared Key/value pairs...
Count of elements now = 0

ให้เราดูตัวอย่างอื่นเพื่อใช้เมธอด Dictionary.ContainsValue() -

ตัวอย่าง

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);
      }
      if (dict.ContainsValue("Angelina"))
         Console.WriteLine("Value found!");
      else
         Console.WriteLine("Value isn't in the dictionary!");
      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);
   }
}

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 isn't in the dictionary!
Cleared Key/value pairs...
Count of elements now = 0