How to Sort a Dictionary by Keys in Swift - Step by Step Examples

How to Sort a Dictionary by Keys in Swift ?

Answer

To sort a dictionary by keys in Swift, you can use the `sorted(by:)` method and a dictionary comprehension. This allows you to create a new dictionary with the key-value pairs sorted by key.

✐ Examples

1 Sorting a Dictionary by Keys Using `sorted(by:)`

We can sort a dictionary by keys in Swift using the `sorted(by:)` method. This example demonstrates how to declare and initialize a dictionary, use the `sorted(by:)` method to sort the dictionary by keys, and print the sorted dictionary.

For example,

We start by declaring and initializing a dictionary named myDictionary with integer keys and string values.
We use the `sorted(by:)` method to get the keys in sorted order.
We use a dictionary comprehension to create a new dictionary with the sorted keys.
We print the sorted dictionary.

Swift Program

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

// Sort the dictionary by keys using sorted(by:)
let sortedDict = Dictionary(uniqueKeysWithValues: myDictionary.sorted(by: { $0.key < $1.key }))

// Print the sorted dictionary
print("Sorted dictionary:")
for (key, value) in sortedDict {
    print("Key: \(key), Value: \(value)")
}

Output

Sorted dictionary:
Key: 1, Value: One
Key: 2, Value: Two
Key: 3, Value: Three

2 Sorting a Dictionary by Keys in Descending Order

We can sort a dictionary by keys in descending order in Swift using the `sorted(by:)` method. This example demonstrates how to declare and initialize a dictionary, use the `sorted(by:)` method to sort the dictionary by keys in descending order, and print the sorted dictionary.

For example,

We start by declaring and initializing a dictionary named myDictionary with integer keys and string values.
We use the `sorted(by:)` method to get the keys in sorted order in descending order.
We use a dictionary comprehension to create a new dictionary with the sorted keys in descending order.
We print the sorted dictionary.

Swift Program

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

// Sort the dictionary by keys in descending order using sorted(by:)
let sortedDict = Dictionary(uniqueKeysWithValues: myDictionary.sorted(by: { $0.key > $1.key }))

// Print the sorted dictionary
print("Sorted dictionary:")
for (key, value) in sortedDict {
    print("Key: \(key), Value: \(value)")
}

Output

Sorted dictionary:
Key: 3, Value: Three
Key: 2, Value: Two
Key: 1, Value: One

Summary

In this tutorial, we learned How to Sort a Dictionary by Keys in Swift language with well detailed examples.

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How to Sort a Dictionary by Keys in Swift - Step by Step Examples