Realm程序示例

import Foundation
import RealmSwift
class RealmManage:ObservableObject{
    private(set) var localRealm:Realm?
    //设置localRealm
    @Published private(set)var tasks:[Task]=[]
    //设置tasks存放展示的数据
    @Published private(set)var temTasks:Set<Task> = []
    @Published private(set)var resultTasks:Set<Task>=[]
    init(){
        openRealm()
        getTasks()
    }
    //每次调用realm时初始化的函数
    func openRealm(){
        do{
            let config = Realm.Configuration(schemaVersion:5) { migration, oldSchemaVersion in
            //当数据库字段更新时，更改schemaVersion版本，数据会自动迁移
                if oldSchemaVersion<5{
                }
            }
            Realm.Configuration.defaultConfiguration = config
            localRealm = try Realm()
        }catch{
            print("Error opening Realm",error)
        }
    }
    func addTask(taskTitle:String,DDL:Date,Duration:Double,Cost:String,isSplit:Bool,Location:String,Status:String){
        if let localRealm = localRealm {
            do{
                try localRealm.write({
                    let newTask = Task(value: ["name":taskTitle])
                    localRealm.add(newTask)
                    getTasks()
                    print("add a new task",newTask)
                })
            }catch{
                print("Error adding task to Realm:\(error)")
            }
        }
    }
    //添加函数
    func getTasks(){
        if let localRealm = localRealm {
            let allTasks = localRealm.objects(Task.self).sorted(byKeyPath: "DDL")
            tasks = []
            allTasks.forEach { task in
                tasks.append(task)
            }
        }
    }
    //得到所有数据的函数
    func updateTaskInfo(id:ObjectId,name:String){
        if let localRealm = localRealm {
            do{
                let taskToUpdate = localRealm.objects(Task.self).filter(NSPredicate(format: "_id == %@", id))
                guard !taskToUpdate.isEmpty else {return}
                try localRealm.write({
                    taskToUpdate[0].name = name
                    getTasks()
                    print("Update task with id\(id)!Completed status:\(name)")
                })
            }catch{
                print("Error updating task\(id) to realm:\(error)")
            }
        }
    }
    //更新数据函数
    func filterTask(cost:String,location:String){
        if let localRealm = localRealm?.objects(Task.self) {
            getTasks()
            var inTasks = Set(tasks)
            if cost != "All" {
                let filtertest = Set(localRealm.where {
                    ($0.Cost == cost)
                })
                temTasks = []
                filtertest.forEach { task in
                    temTasks.insert(task)
                }
                inTasks = inTasks.intersection(temTasks)
                tasks = Array(inTasks)
            }
            if location != "All"{
                let taskToFilter = Set(localRealm.where {
                    ($0.Location == location)
                })
                temTasks = []
                taskToFilter.forEach { task in
                    temTasks.insert(task)
                }
                inTasks = inTasks.intersection(temTasks)
                tasks = Array(inTasks)
            }
            if cost == "All" && location == "All"{
                getTasks()
            }
        }
    }
    //筛选函数
    func deleteTask(id:ObjectId){
        if let localRealm = localRealm {
            do{
                let taskToDelete = localRealm.objects(Task.self).filter(NSPredicate(format: "_id == %@", id))
                guard !taskToDelete.isEmpty else{return}
                try localRealm.write({
                    localRealm.delete(taskToDelete)
                    getTasks()
                    print("Deleted task with id \(id)")
                })
            }catch{
                print("Error deleteing task\(id) to realm\(error)")
            }
        }
    }
}
//删除函数

数据声明

import Foundation
import RealmSwift
import SwiftUI
class Task:Object,ObjectKeyIdentifiable{
    @Persisted (primaryKey: true) var _id:ObjectId
    @Persisted var setDate = Date()
    @Persisted var name = "我是任务名称Missong1"
}

使用

@EnvironmentObject var realmManager:RealmManage

打印数据库文件路径

print(Realm.Configuration.defaultConfiguration.fileURL)