Realm CRUD Swift 5

RealmExample.swift

import UIKit
import RealmSwift

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        
        let realm = try! Realm()
        
        // Save
        let note = Note()
        note.id = incrementID()
        note.title = "Remember the milk!"
        note.text = "Mom asked if I could bring a gallon of milk home."
        
        try! realm.write {
            realm.add(note)
        }
        
        // Retrieve
        let notes = realm.objects(Note.self)
        for note in notes {
            print("title:", note.title)
            print("text:", note.text)
        }
        
        // Update
        let objects = realm.objects(Note.self).filter("title = %@", "Remember the milk!")
        
        if let object = objects.first {
            try! realm.write {
                object.text = "updatedtext"
                object.title = "updatetitle"
            }
        }
 
        // Delete
        if let userObject = realm.objects(Note.self).filter("id == 2").first {
            print("In process of deleting")
            try! realm.write {
                realm.delete(userObject)
            }
            print("Object deleted.")
        }
        else{
            print("Object not found.")
        }
        
    }
    // Simple Incremental ID
    func incrementID() -> Int {
        let realm = try! Realm()
        return (realm.objects(Note.self).max(ofProperty: "id") as Int? ?? 0) + 1
    }

}

class Note: Object {
    @objc dynamic var id = 0
    @objc dynamic var title = ""
    @objc dynamic var created = Date()
    @objc dynamic var text = ""
    
    override static func primaryKey() -> String? {
        return "id"
    }
}