How to Convert a Dictionary to a JSON String in Swift

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,

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)
}

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

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,

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)
}

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