โปรแกรม C# รวม Dictionary สองอัน

กำหนด Dictionary 2 อัน:

Dictionary<string, int> dict1 = new Dictionary<string, int>();
dict1.Add("laptop", 1);
dict1.Add("desktop", 2);
Dictionary<string, int> dict2 = new Dictionary<string, int>();
dict2.Add("desktop", 3);
dict2.Add("tablet", 4);
dict2.Add("mobile", 5);

ใช้ HashSet และ UnionWith() รวม Key:

HashSet<string> hSet = new HashSet<string>(dict1.Keys);
hSet.UnionWith(dict2.Keys);

ตัวอย่าง

using System;
using System.Collections.Generic;
class Program {
    static void Main() {
        Dictionary<string, int> dict1 = new Dictionary<string, int>();
        dict1.Add("laptop", 1);
        dict1.Add("desktop", 2);
        Dictionary<string, int> dict2 = new Dictionary<string, int>();
        dict2.Add("desktop", 3);
        dict2.Add("tablet", 4);
        dict2.Add("mobile", 5);
        HashSet<string> hSet = new HashSet<string>(dict1.Keys);
        hSet.UnionWith(dict2.Keys);
        Console.WriteLine("Merged Dictionary...");
        foreach(string val in hSet) { Console.WriteLine(val); }
    }
}