How to sort array of custom objects by property value in Swift?

To sort an array of custom objects by a property value in Swift, you can use the sort(by:) or sorted(by:) methods provided by Swift's standard library. These methods allow you to define custom sorting logic using closures. Here’s a step-by-step guide on how to achieve this:

Step-by-Step Guide

1. Define Your Custom Object:
   First, define the custom object (struct or class) with the properties you want to sort by. For example, let's define a Person struct with firstName, lastName, and age properties.

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   struct Person {
       let firstName: String
       let lastName: String
       let age: Int
   }

2. Create an Array of Custom Objects:
   Create an array of these custom objects.

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   var people = [
       Person(firstName: "John", lastName: "Smith", age: 25),
       Person(firstName: "Jane", lastName: "Doe", age: 35),
       Person(firstName: "Bob", lastName: "Jones", age: 20)
   ]

3. Sort the Array Using sorted(by:):
   Use the sorted(by:) method to sort the array based on a specific property. For example, to sort by age in ascending order:

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   let sortedPeople = people.sorted { $0.age < $1.age }

   This will sort the people array by the age property in ascending order.

4. Sort the Array Using sort(by:):
   If you want to sort the array in place (modifying the original array), use the sort(by:) method:

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   people.sort { $0.age < $1.age }

Example Code

Here is a complete example demonstrating how to sort an array of Person objects by their age property:

struct Person {
    let firstName: String
    let lastName: String
    let age: Int
}

var people = [
    Person(firstName: "John", lastName: "Smith", age: 25),
    Person(firstName: "Jane", lastName: "Doe", age: 35),
    Person(firstName: "Bob", lastName: "Jones", age: 20)
]

// Sorting the array by age in ascending order
let sortedPeople = people.sorted { $0.age < $1.age }

// Printing the sorted array
for person in sortedPeople {
    print("\(person.firstName) \(person.lastName), Age: \(person.age)")
}

Using Comparable Protocol

For a more reusable approach, you can make your custom object conform to the Comparable protocol. This way, you can use the sort() method directly without needing to pass a closure every time.

1. Conform to Comparable:
   Implement the Comparable protocol in your custom object.

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   struct Person: Comparable {
       let firstName: Str...