数据持久化(一)—–归档 读写 文件路径
最后更新于：2022-04-01 22:58:40
~~~
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]autorelease];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];
/*HMTRootViewController * rootVC = [[HMTRootViewController alloc]init];
self.window.rootViewController = rootVC;
[rootVC release];*/
// 1.获取沙盒文件的主路径
NSLog(@"home = %@",NSHomeDirectory());
// 2.获取Documents的路径(获取Library的路径类似)
NSLog(@"documents = %@", [NSHomeDirectory() stringByAppendingString:@"/Documents"]);
NSLog(@"documents = %@", [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"]);
NSLog(@"documents = %@",[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject]);
// 3.获取tmp的路径(单独的方法,与众不同)
NSLog(@"tmp = %@",NSTemporaryDirectory());
// 4.应用程序包.app-----只有读取的权利,没有修改的权利
NSLog(@".app = %@",[[NSBundle mainBundle] bundlePath]);
NSLog(@"resource = %@",[[NSBundle mainBundle]resourcePath]);
NSLog(@".exec = %@",[[NSBundle mainBundle] executablePath]);
//[self simpleOperationOfApp];
[self complexOperationOfApp];
[self complexArrayOperationOfApp];
return YES;
}
#pragma mark - 简单的数据文件write/read
- (void)simpleOperationOfApp{
#pragma mark 字符串---txt
// 1.获取存储文件的上一级路径
NSString * documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
// 2.拼接一个完整的文件存储路径
NSString * filePath = [documentsPath stringByAppendingPathComponent:@"text.txt"];
// 3.write数据
NSString * saveString = @"我叫胡明涛";
[saveString writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:nil];
// 4.从文件中read
NSString * readString = [NSString stringWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:nil];
NSLog(@"%@",readString);
#pragma mark 数组---plist
NSString * cachesPath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];
NSString * arrayFilePath = [cachesPath stringByAppendingPathComponent:@"names.plist"];
NSArray * writeArray = @[@"吴凯",@"许珍珍",@"左友东"];
[writeArray writeToFile:arrayFilePath atomically:YES];
NSArray * readArray = [NSArray arrayWithContentsOfFile:arrayFilePath];
NSLog(@"%@",readArray);
#pragma mark 字典---plist
NSString * tmpPath = NSTemporaryDirectory();
NSString * dicFilePath = [tmpPath stringByAppendingPathComponent:@"dic.plist"];
NSDictionary * writeDic = @{@"name": @"HMT",@"sex":@"female"};
[writeDic writeToFile:dicFilePath atomically:YES];
NSDictionary * readDic = [NSDictionary dictionaryWithContentsOfFile:dicFilePath];
NSLog(@"%@",readDic);
// 修改数据
[readDic setValue:@"humingtao" forKey:@"name"];
[readDic writeToFile:dicFilePath atomically:YES];
NSLog(@"%@",readDic);
#pragma mark NSData
// 获取图片对象
UIImage * writeImage = [UIImage imageNamed:@"OJ2NMBNXQ1G5_20121120051201760"];
// 图片对象转变为NSData类型
NSData * writeData = UIImagePNGRepresentation(writeImage);
NSString * imageFilePath = [documentsPath stringByAppendingPathComponent:@"美女.png"];
[writeData writeToFile:imageFilePath atomically:YES];
NSData * readData = [NSData dataWithContentsOfFile:imageFilePath];
// imageNamed------图片会存入缓存,下次加载很迅速,但是耗内存,图片一大就嗝屁了
UIImage * readImage = [UIImage imageWithData:readData];
// 从文件路径中找,调用一次就重新加载一次,只是显示图片,不加载到内存(后缀名不要加".")
[UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"美女" ofType:@"png"]];
NSLog(@"%@",readImage);
NSLog(@"%@",[UIImage imageWithContentsOfFile:imageFilePath]);
}
#pragma mark - 单个--复杂的数据对象write/read-------NSCoding协议
- (void)complexOperationOfApp{
UIButton * archiver = [UIButton buttonWithType:UIButtonTypeSystem];
archiver.frame = CGRectMake(20, 100, 100, 40);
[archiver setTitle:@"归档(序列化)" forState:UIControlStateNormal];
[archiver addTarget:self action:@selector(onClickArchiverButton:) forControlEvents:UIControlEventTouchUpInside];
[self.window addSubview:archiver];
UIButton * unArchiver = [UIButton buttonWithType:UIButtonTypeSystem];
unArchiver.frame = CGRectMake(160, 100, 120, 40);
[unArchiver setTitle:@"反归档(反序列化)" forState:UIControlStateNormal];
[unArchiver addTarget:self action:@selector(onClickUnArchiverButton:) forControlEvents:UIControlEventTouchUpInside];
[self.window addSubview:unArchiver];
}
#pragma mark 对复杂的数据对象进行写入操作.原理:复杂的数据对象序列化为NSData,将NSData写入文件,实现数据持久化
- (void)onClickArchiverButton:(UIButton *)button{
/**
* 1.自定义复杂的数据类型,例如ABPerson
* (1)ABPerson必须实现NSCoding协议的方法
* (2)ABPerson中的实例变量或属性,也必须实现NSCoding协议的方法
* (3)ABPerson中的基本数据类型没有过多限制
* 2.创建一个序列化工具对象
* 3.先找路径
* 4.对复杂的数据类型对象进行序列化
* 5.结束 finishEncoding
* 6.NSData写入
*/
HMTABPerson * person = [[HMTABPerson alloc]init];
person.name = @"HMT";
person.age = 25;
NSMutableData * archiverData = [NSMutableData data];
NSKeyedArchiver * archiver = [[NSKeyedArchiver alloc]initForWritingWithMutableData:archiverData];
[archiver encodeObject:person forKey:@"PersonKey"];
[archiver finishEncoding];
NSString * documents = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)lastObject];
NSString * filePath = [documents stringByAppendingPathComponent:@"person.data"];
[archiverData writeToFile:filePath atomically:YES];
[person release];
[archiver release];
}
#pragma mark 从文件中读取数据来实例化复杂对象数据操作
- (void)onClickUnArchiverButton:(UIButton *)button{
/**
* 1.先找路径
* 2.NSData读出
* 3.创建一个反序列化工具
* 4.反序列化
* 5.结束 finishDecoding
* 6.操作对象了
*/
NSString * documents = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)lastObject];
NSString * filePath = [documents stringByAppendingPathComponent:@"person.data"];
NSData * unarchiverData = [NSData dataWithContentsOfFile:filePath];
NSKeyedUnarchiver * unarchiver = [[NSKeyedUnarchiver alloc]initForReadingWithData:unarchiverData];
HMTABPerson * person = [unarchiver decodeObjectForKey:@"PersonKey"];
[unarchiver finishDecoding];
NSLog(@"%@",person.name);
[unarchiver release];
}
#pragma mark - 数组--复杂的数据对象write/read-------NSCoding协议
- (void)complexArrayOperationOfApp{
UIButton * archiver = [UIButton buttonWithType:UIButtonTypeSystem];
archiver.frame = CGRectMake(20, 200, 100, 40);
[archiver setTitle:@"归档(序列化)" forState:UIControlStateNormal];
[archiver addTarget:self action:@selector(onClickArchiverArrayButton) forControlEvents:UIControlEventTouchUpInside];
[self.window addSubview:archiver];
UIButton * unArchiver = [UIButton buttonWithType:UIButtonTypeSystem];
unArchiver.frame = CGRectMake(160, 200, 120, 40);
[unArchiver setTitle:@"反归档(反序列化)" forState:UIControlStateNormal];
[unArchiver addTarget:self action:@selector(onClickUnArchiverArrayButton) forControlEvents:UIControlEventTouchUpInside];
[self.window addSubview:unArchiver];
}
#pragma mark 写入
- (void)onClickArchiverArrayButton{
NSMutableData * archiverData = [NSMutableData data];
NSKeyedArchiver * archiver = [[NSKeyedArchiver alloc]initForWritingWithMutableData:archiverData];
HMTABPerson * person1 = [[HMTABPerson alloc]init];
person1.name = @"陈凤长";
person1.age = 24;
HMTABPerson * person2 = [[HMTABPerson alloc]init];
person2.name = @"胡明涛";
person2.age = 24;
NSArray * personArray = @[person1,person2];
[archiver encodeObject:personArray forKey:@"PersonArrayKey"];
[archiver finishEncoding];
NSString * tmpPath = NSTemporaryDirectory();
NSString * filePath = [tmpPath stringByAppendingPathComponent:@"personArray.plist"];
[archiverData writeToFile:filePath atomically:YES];
[person1 release];
[person2 release];
[archiver release];
}
#pragma mark 读取
- (void)onClickUnArchiverArrayButton{
NSString * tmpPath = NSTemporaryDirectory();
NSString * filePath = [tmpPath stringByAppendingPathComponent:@"personArray.plist"];
NSData * unarchiverData = [NSData dataWithContentsOfFile:filePath];
NSKeyedUnarchiver * unarchiver = [[NSKeyedUnarchiver alloc]initForReadingWithData:unarchiverData];
NSArray * personArray = [unarchiver decodeObjectForKey:@"PersonArrayKey"];
[unarchiver finishDecoding];
HMTABPerson * person1 = [personArray objectAtIndex:0];
HMTABPerson * person2 = [personArray objectAtIndex:1];
NSLog(@"%@ %@",person1.name,person2.name);
[unarchiver release];
}
~~~
HMTABPerson.h
~~~
#import
@interface HMTABPerson : NSObject
@property (nonatomic,assign)int age;
@property (nonatomic,copy) NSString * name;
@end
~~~
HMTABPerson.m
~~~
#import "HMTABPerson.h"
@implementation HMTABPerson
- (void)dealloc{
[_name release];
[super dealloc];
}
// 序列化,编码
- (void)encodeWithCoder:(NSCoder *)aCoder{
[aCoder encodeObject:_name forKey:@"NameKey"];
[aCoder encodeInt:_age forKey:@"AgeKey"];
}
// 反序列化,解码
- (id)initWithCoder:(NSCoder *)aDecoder{
if (self = [super init]) {
self.name = [aDecoder decodeObjectForKey:@"NameKey"];
self.age = [aDecoder decodeIntForKey:@"AgeKey"];
}
return self;
}
@end
~~~
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