一、创建Coredata有两种方式，一种是创建项目的时候创建，另一种是直接command +N选择Coredata创建
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二、创建CoreData工具类CodataTool.swift
//
// CodataTool.swift
// PricingExcellence
//
// Created by Mr_怪蜀黍 on 2017/7/11.
// Copyright © 2017年 LW. All rights reserved.
//
import UIKit
import CoreData
class CodataTool: NSObject {
/*
* 通过AppDelegate单利来获取管理的数据上下文对象，操作实际内容
* 通过NSEntityDescription.insertNewObjectForEntityForName方法创建实体对象
* 给实体对象赋值
* 通过saveContext()保存实体对象
*/
func SavaDataToCoredataWith(entity:String, dataDic:NSDictionary){
do{
//获取数据对象
var myContext : NSManagedObjectContext!;
if #available(iOS 10.0, *) {
myContext = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext
} else {
myContext = (UIApplication.shared.delegate as! AppDelegate).managedObjectContext
}
let inserInfo = NSEntityDescription.insertNewObject(forEntityName: entity, into: myContext);
for (key, value) in dataDic { // 遍历字典中的所有key value
inserInfo.setValue(value, forKey: key as! String);
}
try myContext.save()
print("保存数据成功")
}catch{
fatalError();
}
}
/*
查询数据
*/
func getDataFromCoredataWith(entity:String , key:NSString)->Any{
//获取数据对象
var myContext : NSManagedObjectContext!;
//声明数据的请求
let request = NSFetchRequest<NSFetchRequestResult>(entityName: entity);
if #available(iOS 10.0, *) {
myContext = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext
} else {
myContext = (UIApplication.shared.delegate as! AppDelegate).managedObjectContext
}
var requestData :Any?
do{
let dataList = try myContext.fetch(request) as! [NSManagedObject];
for data in dataList as![Product] {
if data.product_id == key.intValue{
requestData = data
return requestData as Any
}else{
requestData = ""
}
}
}catch{
fatalError();
}
return requestData as Any
}
//清除coreData中的数据
func deleteCoreDataWit(entity:String){
//获取数据对象
var myContext : NSManagedObjectContext!;
//声明数据的请求
let request = NSFetchRequest<NSFetchRequestResult>(entityName: entity);
if #available(iOS 10.0, *) {
myContext = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext
} else {
myContext = (UIApplication.shared.delegate as! AppDelegate).managedObjectContext
}
do{
let rels = try myContext.fetch(request) as! [NSManagedObject];
for rel in rels{
myContext.delete(rel);
}
try myContext.save();
print("删除数据成功")
}catch{
fatalError();
}
}
/**本地文件的读写*/
func setProductNameData(){
//取得txt文件路径
let path = Bundle.main.path(forResource: "ProductName", ofType: "txt")!
print (path)
//设定路径
let url: NSURL = NSURL(fileURLWithPath: path)
// //定义可变数据变量
// let data = NSMutableData()
// //向数据对象中添加文本，并制定文字code
// data.append("Hello Swift".data(using: String.Encoding.utf8, allowLossyConversion: true)!)
// //用data写文件
// data.write(toFile: url.path!, atomically: true)
//从url里面读取数据，读取成功则赋予readData对象，读取失败则走else逻辑
if let readData = NSData(contentsOfFile: url.path!) {
//如果内容存在 则用readData创建文字列
// print((data: readData as Data, encoding: String.Encoding.utf8.rawValue))
let dataString:NSString = NSString.init(data: readData as Data, encoding: String.Encoding.utf8.rawValue) as Any as! NSString
print(dataString)
let array: [Any] = dataString.components(separatedBy: "\n")
for index in 1...55{
print(array[index-1])
let dic:NSDictionary = ["name":array[index-1],"product_id":index]
self.SavaDataToCoredataWith(entity: "Product", dataDic: dic)
}
} else {
//nil的话，输出空
print("Null")
}
}
}
三、在AppDelegate.swift中关联CoreData
func applicationWillTerminate(_ application: UIApplication) {
if #available(iOS 10.0, *) {
self.saveContext()
} else {
// Fallback on earlier versions
}
}
// MARK: - Core Data stack
@available(iOS 10.0 , *)
lazy var persistentContainer: NSPersistentContainer = {
let container = NSPersistentContainer(name: "ProductCodata")
container.loadPersistentStores(completionHandler: { (storeDescription, error) in
if let error = error as NSError? {
fatalError("Unresolved error \(error), \(error.userInfo)")
}
})
return container
}()
lazy var applicationDocumentsDirectory: URL = {
let urls = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
return urls[urls.count-1]
}()
lazy var managedObjectModel: NSManagedObjectModel = {
let modelURL = Bundle.main.url(forResource: "ProductCodata", withExtension: "momd")!
return NSManagedObjectModel(contentsOf: modelURL)!
}()
lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator = {
let coordinator = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)
let url = self.applicationDocumentsDirectory.appendingPathComponent("ProductCodata.sqlite")
var failureReason = "There was an error creating or loading the application's saved data."
do {
try coordinator.addPersistentStore(ofType: NSSQLiteStoreType, configurationName: nil, at: url, options: nil)
} catch {
// Report any error we got.
var dict = [String: AnyObject]()
dict[NSLocalizedDescriptionKey] = "Failed to initialize the application's saved data" as AnyObject?
dict[NSLocalizedFailureReasonErrorKey] = failureReason as AnyObject?
dict[NSUnderlyingErrorKey] = error as NSError
let wrappedError = NSError(domain: "YOUR_ERROR_DOMAIN", code: 9999, userInfo: dict)
NSLog("Unresolved error \(wrappedError), \(wrappedError.userInfo)")
abort()
}
return coordinator
}()
lazy var managedObjectContext: NSManagedObjectContext = {
let coordinator = self.persistentStoreCoordinator
var managedObjectContext = NSManagedObjectContext(concurrencyType: .mainQueueConcurrencyType)
managedObjectContext.persistentStoreCoordinator = coordinator
return managedObjectContext
}()
// MARK: - Core Data Saving support
@available(iOS 10.0 , *)
func saveContext () {
let context = persistentContainer.viewContext
if context.hasChanges {
do {
try context.save()
} catch {
let nserror = error as NSError
fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
}
}
}
四、关于多表的关联
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