Convert a Dictionary to a String in C#

This post will discuss how to convert a Dictionary<TKey,TValue> to a string in C#.

1. Using `String.Join()` method

The String.Join() method from the System.Linq namespace is commonly used to concatenate elements of the specified sequence using the specified separator. You can use the Select() method as a helper while joining each key-value pair in a dictionary with a delimiter.

using System;

using System.Linq;

using System.Collections.Generic;

public static class Extensions

{

public static string GetString<K,V>(this IDictionary<K,V> dict)

{

var items = dict.Select(kvp => kvp.ToString());

return string.Join(", ", items);

}

public class Example

{

public static void Main()

{

Dictionary<string, int> dict = new Dictionary<string, int>() {

{"A", 1}, {"B", 2}, {"C", 3}, {"D", 4}, {"E", 5}

};

string str = dict.GetString();

Console.WriteLine(str); // [A, 1], [B, 2], [C, 3], [D, 4], [E, 5]

}

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Instead of calling the ToString() method, you can format the key-value pair as desired. The following solution demonstrates this by using the LINQ Query syntax to project over the dictionary mappings.

using System;

using System.Linq;

using System.Collections.Generic;

public static class Extensions

{

public static string GetString<K,V>(this IDictionary<K,V> dict)

{

var items = from kvp in dict

select kvp.Key + ":" + kvp.Value;

return "{" + string.Join(", ", items) + "}";

}

public class Example

{

public static void Main()

{

Dictionary<string, int> dict = new Dictionary<string, int>() {

{"A", 1}, {"B", 2}, {"C", 3}, {"D", 4}, {"E", 5}

};

string str = dict.GetString();

Console.WriteLine(str); // {A:1, B:2, C:3, D:4, E:5}

}

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2. Using `Enumerable.Aggregate()` method

Alternatively, you can use the LINQ’s Aggregate() method, which applies an accumulator function on each element of a sequence. It can be used as follows to stringify a dictionary.

using System;

using System.Linq;

using System.Collections.Generic;

public static class Extensions

{

public static string GetString<K,V>(this IDictionary<K,V> dict)

{

return dict.Select(kvp => kvp.ToString())

.Aggregate((x, y) => x + ", " + y);

}

public class Example

{

public static void Main()

{

Dictionary<string, int> dict = new Dictionary<string, int>() {

{"A", 1}, {"B", 2}, {"C", 3}, {"D", 4}, {"E", 5}

};

string str = dict.GetString();

Console.WriteLine(str); // [A, 1], [B, 2], [C, 3], [D, 4], [E, 5]

}

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3. Using `StringBuilder.Append()` method

Finally, you can write your custom logic to stringify a dictionary. The idea is to iterate over the dictionary using a foreach loop and append all the dictionary entries to a StringBuilder using its Append() method. Then, invoke the ToString() method to get the string representation.

using System;

using System.Linq;

using System.Text;

using System.Collections.Generic;

public static class Extensions

{

public static string GetString<K,V>(this IDictionary<K,V> dict)

{

var sb = new StringBuilder();

foreach (var pair in dict) {

sb.Append(String.Format("[{0}:{1}] ", pair.Key, pair.Value));

}

return sb.ToString();

}

public class Example

{

public static void Main()

{

Dictionary<string, int> dict = new Dictionary<string, int>() {

{"A", 1}, {"B", 2}, {"C", 3}, {"D", 4}, {"E", 5}

};

string str = dict.GetString();

Console.WriteLine(str); // [A:1] [B:2] [C:3] [D:4] [E:5]

}

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That’s all about converting a Dictionary<TKey,TValue> to a string in C#.

Convert a Dictionary to a String in C#

1. Using String.Join() method

2. Using Enumerable.Aggregate() method

3. Using StringBuilder.Append() method

1. Using `String.Join()` method

2. Using `Enumerable.Aggregate()` method

3. Using `StringBuilder.Append()` method