How to Convert a Dictionary to a JSON String in Swift - Step by Step Examples

How to Convert a Dictionary to a JSON String in Swift ?

Answer

To convert a dictionary to a JSON string in Swift, you can use the `JSONSerialization` class. This allows you to create a JSON string representation of the dictionary.

✐ Examples

1 Converting a Dictionary to a JSON String Using `JSONSerialization`

We can convert a dictionary to a JSON string in Swift using the `JSONSerialization` class. This example demonstrates how to declare and initialize a dictionary, use the `JSONSerialization.data(withJSONObject:options:)` method to convert the dictionary to a JSON string, and print the resulting JSON string.

For example,

We start by declaring and initializing a dictionary named myDictionary with integer keys and string values.
We use the `JSONSerialization.data(withJSONObject:options:)` method to convert the dictionary to a JSON string.
We print the resulting JSON string.

Swift Program

import Foundation

let myDictionary: [Int: String] = [
    1: "One",
    2: "Two",
    3: "Three"
]

// Convert the dictionary to a JSON string using JSONSerialization
if let jsonData = try? JSONSerialization.data(withJSONObject: myDictionary, options: .prettyPrinted),
   let jsonString = String(data: jsonData, encoding: .utf8) {
    // Print the resulting JSON string
    print("JSON string:")
    print(jsonString)
}

Output

JSON string:
{
  "1" : "One",
  "2" : "Two",
  "3" : "Three"
}

2 Converting a Dictionary with Complex Values to a JSON String

We can convert a dictionary with complex values to a JSON string in Swift using the `JSONSerialization` class. This example demonstrates how to declare and initialize a dictionary with complex values, use the `JSONSerialization.data(withJSONObject:options:)` method to convert the dictionary to a JSON string, and print the resulting JSON string.

For example,

We start by declaring and initializing a dictionary named myDictionary with integer keys and values that are dictionaries.
We use the `JSONSerialization.data(withJSONObject:options:)` method to convert the dictionary to a JSON string.
We print the resulting JSON string.

Swift Program

import Foundation

let myDictionary: [Int: [String: Any]] = [
    1: ["name": "John", "age": 30],
    2: ["name": "Jane", "age": 25]
]

// Convert the dictionary to a JSON string using JSONSerialization
if let jsonData = try? JSONSerialization.data(withJSONObject: myDictionary, options: .prettyPrinted),
   let jsonString = String(data: jsonData, encoding: .utf8) {
    // Print the resulting JSON string
    print("JSON string:")
    print(jsonString)
}

Output

JSON string:
{
  "1" : {
    "name" : "John",
    "age" : 30
  },
  "2" : {
    "name" : "Jane",
    "age" : 25
  }
}

Summary

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

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How to Convert a Dictionary to a JSON String in Swift - Step by Step Examples