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

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

For example,

import Foundation

let jsonString = "{\"1\":\"One\",\"2\":\"Two\",\"3\":\"Three\"}"

// Convert the JSON string to a dictionary using JSONSerialization
if let jsonData = jsonString.data(using: .utf8),
   let myDictionary = try? JSONSerialization.jsonObject(with: jsonData, options: []) as? [String: String] {
    // Print the resulting dictionary
    print("Dictionary from JSON string:")
    for (key, value) in myDictionary {
        print("Key: \(key), Value: \(value)")
    }
}

Dictionary from JSON string:
Key: 1, Value: One
Key: 2, Value: Two
Key: 3, Value: Three

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

For example,

import Foundation

let jsonString = "{\"1\":{\"name\":\"John\",\"age\":30},\"2\":{\"name\":\"Jane\",\"age\":25}}"

// Convert the JSON string to a dictionary using JSONSerialization
if let jsonData = jsonString.data(using: .utf8),
   let myDictionary = try? JSONSerialization.jsonObject(with: jsonData, options: []) as? [String: [String: Any]] {
    // Print the resulting dictionary
    print("Dictionary from JSON string:")
    for (key, value) in myDictionary {
        print("Key: \(key), Value: \(value)")
    }
}

Dictionary from JSON string:
Key: 1, Value: {"name": "John", "age": 30}
Key: 2, Value: {"name": "Jane", "age": 25}