How to Iterate Over a Dictionary of Dictionaries in C# - Step by Step Examples

How to Iterate Over a Dictionary of Dictionaries in C# ?

Answer

To iterate over a dictionary of dictionaries in C#, you can use nested `foreach` loops to iterate through both the outer dictionary and the inner dictionaries. This allows you to access and process each key-value pair in the nested dictionaries.

✐ Examples

1 Iterating Over a Dictionary of Dictionaries Using Nested `foreach` Loops

We can iterate over a dictionary of dictionaries in C# using nested `foreach` loops. This example demonstrates how to declare and initialize a dictionary of dictionaries, use nested `foreach` loops to iterate through the outer and inner dictionaries, and print each key-value pair.

For example,

We start by including the necessary namespace: using System.Collections.Generic;.
We declare and initialize a dictionary of dictionaries named outerDict with integer keys and string values.
We use nested `foreach` loops to iterate through the outer and inner dictionaries.
We print each key-value pair.

C# Program

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        // Declare and initialize a dictionary of dictionaries
        Dictionary<string, Dictionary<string, int>> outerDict = new Dictionary<string, Dictionary<string, int>>
        {
            { "A", new Dictionary<string, int> { { "X", 1 }, { "Y", 2 } } },
            { "B", new Dictionary<string, int> { { "Z", 3 } } }
        };

        // Iterate over the dictionary of dictionaries using nested foreach loops
        Console.WriteLine("Iterating over dictionary of dictionaries:");
        foreach (var outerKvp in outerDict)
        {
            Console.WriteLine("Outer Key: {0}", outerKvp.Key);
            foreach (var innerKvp in outerKvp.Value)
            {
                Console.WriteLine("  Inner Key: {0}, Value: {1}", innerKvp.Key, innerKvp.Value);
            }
        }
    }
}

Output

Iterating over dictionary of dictionaries:
Outer Key: A
  Inner Key: X, Value: 1
  Inner Key: Y, Value: 2
Outer Key: B
  Inner Key: Z, Value: 3

2 Iterating Over a Dynamically Created Dictionary of Dictionaries

We can iterate over a dynamically created dictionary of dictionaries in C# using nested `foreach` loops. This example demonstrates how to declare a dictionary of dictionaries, add inner dictionaries dynamically, add key-value pairs to the inner dictionaries, use nested `foreach` loops to iterate through the outer and inner dictionaries, and print each key-value pair.

For example,

We start by including the necessary namespace: using System.Collections.Generic;.
We declare a dictionary of dictionaries named outerDict.
We add inner dictionaries dynamically and add key-value pairs to the inner dictionaries.
We use nested `foreach` loops to iterate through the outer and inner dictionaries.
We print each key-value pair.

C# Program

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        // Declare a dictionary of dictionaries
        Dictionary<string, Dictionary<string, int>> outerDict = new Dictionary<string, Dictionary<string, int>>();

        // Add inner dictionaries dynamically
        outerDict["A"] = new Dictionary<string, int>();
        outerDict["B"] = new Dictionary<string, int>();

        // Add key-value pairs to the inner dictionaries
        outerDict["A"]["X"] = 1;
        outerDict["A"]["Y"] = 2;
        outerDict["B"]["Z"] = 3;

        // Iterate over the dictionary of dictionaries using nested foreach loops
        Console.WriteLine("Iterating over dictionary of dictionaries:");
        foreach (var outerKvp in outerDict)
        {
            Console.WriteLine("Outer Key: {0}", outerKvp.Key);
            foreach (var innerKvp in outerKvp.Value)
            {
                Console.WriteLine("  Inner Key: {0}, Value: {1}", innerKvp.Key, innerKvp.Value);
            }
        }
    }
}

Output

Iterating over dictionary of dictionaries:
Outer Key: A
  Inner Key: X, Value: 1
  Inner Key: Y, Value: 2
Outer Key: B
  Inner Key: Z, Value: 3

Summary

In this tutorial, we learned How to Iterate Over a Dictionary of Dictionaries in C# language with well detailed examples.

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How to Iterate Over a Dictionary of Dictionaries in C# - Step by Step Examples