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C# / .NET - get random key value element from dictionary
12 points
In C# / .NET Dictionary class is Java HashMap class equivalent - see this post.
Quick solution:
Note: below example uses Linq, so include it with:
using System.Linq.
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Random random = new Random();2
Dictionary<string, int> dictionary = ...3
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int index = random.Next(dictionary.Count);5
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string key = dictionary.Keys.ElementAt(index);7
int value = dictionary.Values.ElementAt(index);8
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KeyValuePair<string, int> pair = dictionary.ElementAt(index);Take a look at the example below:
In this section you can find full example that uses Linq method.
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using System;2
using System.Collections.Generic;3
using System.Linq;4
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class Program6
{7
public static void Main(string[] args)8
{9
Random random = new Random();10
Dictionary<string, int> dictionary = new Dictionary<string, int>();11
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dictionary.Add("a", 11);13
dictionary.Add("b", 22);14
dictionary.Add("c", 33);15
dictionary.Add("d", 44);16
dictionary.Add("e", 55);17
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for (int i = 0; i < 10; ++i)19
{20
int index = random.Next(dictionary.Count);21
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//string key = dictionary.Keys.ElementAt(index);23
//int value = dictionary.Values.ElementAt(index);24
KeyValuePair<string, int> pair = dictionary.ElementAt(index);25
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Console.WriteLine("key: " + pair.Key + ", value: " + pair.Value);27
}28
}29
}Output:
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key: e, value: 552
key: e, value: 553
key: d, value: 444
key: b, value: 225
key: c, value: 336
key: a, value: 117
key: b, value: 228
key: b, value: 229
key: a, value: 1110
key: d, value: 44Note: in above example Enuberable.ElementAt Linq method has been used to get element.
