ContainsKey can be used to test keys before inserting them : Dictionary « Collections Data Structure « C# / C Sharp






ContainsKey can be used to test keys before inserting them

  


using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        Dictionary<string, string> openWith = new Dictionary<string, string>();
        openWith.Add("A", "a");
        openWith.Add("B", "b");
        openWith.Add("C", "c");

        if (!openWith.ContainsKey("W"))
        {
            openWith.Add("W", "w");
            Console.WriteLine("Value added ");
        }

   }
}

   
    
  








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