How to Convert a Map to a JSON String in Kotlin


How to Convert a Map to a JSON String in Kotlin ?

Answer

To convert a map to a JSON string in Kotlin, you can use the kotlinx.serialization library. This library provides an easy way to serialize and deserialize Kotlin objects, including maps, to and from JSON strings.



✐ Examples

1 Converting a Map to a JSON String

We can convert a map to a JSON string in Kotlin using the kotlinx.serialization library's Json.encodeToString function.

For example,

  1. We start by adding the kotlinx.serialization library to our project dependencies. If using Gradle, include the serialization dependencies in your build.gradle.kts file.
  2. We import the necessary classes from the kotlinx.serialization and kotlinx.serialization.json packages.
  3. We declare and initialize a map named myMap with key-value pairs.
  4. We create an instance of the Json class.
  5. We convert the map to a JSON string using the Json.encodeToString function.
  6. We print the resulting JSON string to the console using println.

Kotlin Program

import kotlinx.serialization.encodeToString
import kotlinx.serialization.json.Json

fun main() {
    // Declare and initialize a map
    val myMap = mapOf(
        1 to 10,
        2 to 20,
        3 to 30,
        4 to 40,
        5 to 50
    )

    // Create an instance of the Json class
    val json = Json

    // Convert the map to a JSON string
    val jsonString = json.encodeToString(myMap)

    // Print the resulting JSON string
    println("JSON string from map: $jsonString")
}

Output

JSON string from map: {"1":10,"2":20,"3":30,"4":40,"5":50}

Summary

In this tutorial, we learned How to Convert a Map to a JSON String in Kotlin language with well detailed examples.




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  24. How to Sort a Map by Keys in Kotlin ?
  25. How to Sort a Map by Values in Kotlin ?
  26. How to Filter a Map Based on Keys in Kotlin ?
  27. How to Filter a Map Based on Values in Kotlin ?
  28. How to Reduce Values in a Map to a Single Value in Kotlin ?
  29. How to Convert an Array of Key-Value Pairs to a Map in Kotlin ?
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