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//
// ViewController.swift
// Dome2test
//
// Created by 郭文亮 on 2018/11/21.
// Copyright © 2018年 finalliang. All rights reserved.
//
import UIKit
//引入持久化框架
import CoreData
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
test1()
print("----------------------------")
print("----------------------------")
test2()
print("----------------------------")
print("----------------------------")
test3()
print("----------------------------")
print("----------------------------")
test4()
}
//产出数据
func test4() {
//获得当前程序的应用代理
let appdelegate:AppDelegate = UIApplication.shared.delegate as! AppDelegate
//通过应用代理对象。获得管理对象上下文
let managedobjectCOntext = appdelegate.persistentContainer.viewContext
//通过管理对象上下文获得一条实体对象
let newUser = NSEntityDescription.entity(forEntityName: "User", in: managedobjectCOntext)
//创建一个数据提取请求对象
let request:NSFetchRequest = NSFetchRequest<User>(entityName: "User")
request.fetchOffset = 0
request.fetchLimit = 10
request.entity = newUser
do {
//执行管理对象上下文的数据提取操作 将提取结果存入数组
let results:[AnyObject]? = try managedobjectCOntext.fetch(request)
for user:User in results as![User] {
managedobjectCOntext.delete(user)
print("删除")
}
try managedobjectCOntext.save()
let results2:[AnyObject]? = try managedobjectCOntext.fetch(request)
for user:User in results2 as![User] {
print("userName=\(user.userName!)")
print("password=\(user.password!)")
}
} catch {
print("删除失败.")
}
}
//修改编辑数据
func test3() {
//获得当前程序的应用代理
let appdelegate:AppDelegate = UIApplication.shared.delegate as! AppDelegate
//通过应用代理对象。获得管理对象上下文
let managedobjectCOntext = appdelegate.persistentContainer.viewContext
//通过管理对象上下文获得一条实体对象
let newUser = NSEntityDescription.entity(forEntityName: "User", in: managedobjectCOntext)
//创建一个数据提取请求对象
let request:NSFetchRequest = NSFetchRequest<User>(entityName: "User")
request.fetchOffset = 0
request.fetchLimit = 10
request.entity = newUser
do {
//执行管理对象上下文的数据提取操作 将提取结果存入数组
let results:[AnyObject]? = try managedobjectCOntext.fetch(request)
for user:User in results as![User] {
user.userName = "guoguoguo"
}
try managedobjectCOntext.save()
let results2:[AnyObject]? = try managedobjectCOntext.fetch(request)
for user:User in results2 as![User] {
print("userName=\(user.userName!)")
print("password=\(user.password!)")
}
} catch {
print("failed to modify data.")
}
}
//查找数据
func test2() {
//获得当前程序的应用代理
let appdelegate:AppDelegate = UIApplication.shared.delegate as! AppDelegate
//通过应用代理对象。获得管理对象上下文
let managedobjectCOntext = appdelegate.persistentContainer.viewContext
//通过管理对象上下文获得一条实体数据
let newUser = NSEntityDescription.entity(forEntityName: "User", in: managedobjectCOntext)
//创建一个数据提取请求对象
let request = NSFetchRequest<User>(entityName: "User")
//设置提取数据的偏移值
request.fetchOffset = 0
//设置提取数据的数量
request.fetchLimit = 10
//设置需要提取数据的实体对象
request.entity = newUser
//创建一个谓词对象 设置提取数据的查询条件
// let predicate = NSPredicate(format: "userName= 'john' ", "")
// let predicate = NSPredicate(format: "", "")
//设置数据提取请求对象的谓词属性
// request.predicate = predicate
//查询
do {
//数据提取。把结果存在数组中
let items = try managedobjectCOntext.fetch(request)
for user:User in items {
print("userName=\(user.userName!)")
print("password=\(user.password!)")
}
} catch {
print("获取数据失败")
}
}
//插入数据
func test1() {
//获得当前程序的应用代理
let appdelegate:AppDelegate = UIApplication.shared.delegate as! AppDelegate
//通过应用代理对象。获得管理对象上下文
let managedobjectCOntext = appdelegate.persistentContainer.viewContext
//通过管理对象上下文插入一条实体数据
let newUser = NSEntityDescription.insertNewObject(forEntityName: "User", into: managedobjectCOntext) as! User
newUser.userName = "john"
newUser.password = "111"
do {
try managedobjectCOntext.save()
print("保存成功")
} catch {
print("保存失败")
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}