//把数据存到硬盘
//iOS, 沙盒机制
//1.系统会为每个app, 分配一个文件夹(沙盒)
//2.每个app, 只能访问自己的沙盒; 系统的相册, 视频, 短信, 通讯录, 是可以访问的, 前提: 需要申请权限
//沙盒路径
//1.沙盒主目录, 名字无规律, 能避免别的应用访问
NSString *sandBoxPath = NSHomeDirectory();
NSLog(@"%@", sandBoxPath);
//1.
NSString *documentPath = [sandBoxPath stringByAppendingString:@"/Documents"];
//2.
//NSString *documentsPath1 = [sandBoxPath stringByAppendingPathComponent:@"Documents"];
//3.
//NSString *documengsPath2 = [NSString stringWithFormat:@"%@/Documents", sandBoxPath];
NSLog(@"%@", documentPath);
//沙盒主目录里有三个文件夹
//1.Documents: 存储一些比较重要的数据, 比如: 游戏存档, 用户信息等重要文件
//注: Documents中的文件, 在同步到iCloud的时候会一并同步进去, 所以要求Docements中的文件不能过大, 否则app没办法通过审核, 进而无法在appStore上线
//查找文件夹方法
//参数1: 文件夹名称
//参数2: 搜索的区域, 只在用户域(NSUserDomainMask)
//参数3: 返回的路径 是 相对路径no 还是 绝对路径yes, 使用绝对路径
NSString *documentsPath3 = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
NSLog(@"%@", documentsPath3);
//2.Library, 存放视频, 图片, 音频, 缓存, 配置等文件
NSString *libraryPath = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) firstObject];
NSLog(@"%@", libraryPath);
//Library. 有两个子文件夹
//a.Caches, 缓存文件
NSString *cachesPath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) firstObject];
NSLog(@"%@", cachesPath);
//b.Preferences, 配置文件
//没有提供查找路径的方法, 不会直接在文件夹中对文件进行修改, 而是是Xcode中进行修改, 系统会自动同步到Preferences中去
//3.tmp, 临时文件文件, 比如zip压缩包
NSString *tmpPath = NSTemporaryDirectory();
NSLog(@"%@", tmpPath);
//4.包, 程序编译后, 最终形成一个包(比如*.app), 包内的文件是只读, 不能修改; Xcode中添加的文件, 比如图片, 文档等, 最终都会放到包中
NSString *bundlePath = [[NSBundle mainBundle] bundlePath];
NSLog(@"%@", bundlePath);
//数据持久化方式(这个是存到配置文件tmp中)
//1.文件读写
//2.NSUserDefaults
//3.归档
//4.数据库
//5.CoreData
//读取数据的方法
//documents文件路径
NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
//文件路径
NSString *filePath = [documentsPath stringByAppendingPathComponent:@"money.txt"];
NSError *error = nil;
NSString *moneyString = [[NSString alloc] initWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:&error];
if (error) {
NSLog(@"读取失败:%@", error);
}else{
NSLog(@"读取成功");
self.money = [moneyString integerValue];
self.label.text = [NSString stringWithFormat:@"%ld", self.money];
}
//1. 文件读写
//适用范围: 简单地数据, NSString, NSArray, NSDictionary, NSData以及他们的子类
//NSString
//写入文件
//- WriteToFile:atomically:encoding:error:
//读取文件
//initWithContentsOfFile: encoding: error:
//NSArray
//写入文件
//writeToFile: atomically:
//读取文件
//initWithContentsOfFile:(也有便利构造器)
NSArray *array = @[@"校花", @"校草", @"笑话"];
//写入文件
NSString *libraryPath1 = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) firstObject];
NSString *filePath1 = [libraryPath1 stringByAppendingPathComponent:@"array.txt"];
BOOL result = [array writeToFile:filePath1 atomically:YES];
if (result) {
NSLog(@"写入成功");
}else{
NSLog(@"写入失败");
}
//读取文件内容
NSArray *array1 = [[NSArray alloc] initWithContentsOfFile:filePath1];
//NSArray *array1 = [NSArray arrayWithContentsOfFile:filePath1];
for (NSString *string in array1) {
NSLog(@"%@", string);
}
[array1 release];
//NSDictionary
//写入文件
NSDictionary *dic = @{@"name" : @"校花", @"age" : @"18", @"class" : @"24"};
//写入文件
NSString *cachesPath1 = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) firstObject];
NSString *filePath2 = [cachesPath1 stringByAppendingPathComponent:@"girl.plist"];
BOOL result2 = [dic writeToFile:filePath2 atomically:YES];
if (result2) {
NSLog(@"写入成功");
}else{
NSLog(@"写入失败");
}
//注: Array 和 Dictionary的数据, 建议存的文件使用后缀plist, 这样看起来比较直观
NSDictionary *dic2 = [[NSDictionary alloc] initWithContentsOfFile:filePath2];
NSLog(@"%@", dic2);
[dic2 release];
//NSDictionary
//写入文件
//writeToFile: atomically:
//读取文件
//initWithContentsOfFile:(也有便利构造器)
//NSData
//写入文件
//writeToFile: atomically:
//读取文件
//initWithContentsOfFile:(也有便利构造器)
NSString *str = @"iOS";
NSData *data = [str dataUsingEncoding:NSUTF8StringEncoding];
NSString *tmpPath3 = NSTemporaryDirectory();
NSString *filePath3 = [tmpPath3 stringByAppendingPathComponent:@"data.txt"];
BOOL result3 = [data writeToFile:filePath3 atomically:YES];
if (result3) {
NSLog(@"写入成功");
}else{
NSLog(@"写入失败");
}
NSData *data3 = [[NSData alloc] initWithContentsOfFile:filePath3];
NSString *string3 = [[NSString alloc] initWithData:data3 encoding:NSUTF8StringEncoding];
NSLog(@"%@", string3);
//NSUserDefaults, 系统封装的一个快速写入内容的一个类, 单例模式, 继承于NSObject
//使用范围: BOOL, float, double, NSInteger
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
//写入文件
//BOOL
[userDefaults setBool:YES forKey:@"isFirst"];
[userDefaults setInteger:100 forKey:@"age"];
[userDefaults setFloat:99.9 forKey:@"price"];
[userDefaults setDouble:10.00 forKey:@"weight"];
[userDefaults setObject:@"zhangsan" forKey:@"name"];
//同步
[userDefaults synchronize];
//读取内容
BOOL boolValue = [userDefaults boolForKey:@"isFirst"];
NSLog(@"%d", boolValue);
NSInteger age = [userDefaults integerForKey:@"age"];
NSLog(@"%ld", age);
CGFloat weight =[userDefaults doubleForKey:@"weight"];
NSLog(@"%.2lf", weight);
CGFloat price = [userDefaults floatForKey:@"price"];
NSLog(@"%.2lf", price);
NSString *name =[userDefaults objectForKey:@"name"];
NSLog(@"%@", name);
//3.归档
//适用范围: 主要用于存自定义的数据类型, 比如Person
Person *person = [[Person alloc] init];
person.name = @"校花";
person.age = @"18";
person.gender = @"女";
//NSKeyedArchiver, 压缩工具, 继承于NSCoder, 把一个对象进行编码, 转化成NSData
NSMutableData *mData = [[NSMutableData alloc] initWithCapacity:0];
NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:mData];
//把person对象压进data
[archiver encodeObject:person forKey:@"girlFriend"];
//完成压缩
[archiver finishEncoding];
//tmp, 临时文件文件, 比如zip压缩包(写入文件（自定义一个路径）)
NSString *tmpPath1 = NSTemporaryDirectory();
NSString *filePath5 = [tmpPath1 stringByAppendingPathComponent:@"person.txt"];
BOOL result5 = [mData writeToFile:filePath5 atomically:YES];
if (result5) {
NSLog(@"写入成功");
}else{
NSLog(@"写入失败");
}
//反归档
NSData *mData1 = [[NSData alloc] initWithContentsOfFile:filePath5];
//NSKeyedUnarchiver, 解压工具, 从data数据提取对象
NSKeyedUnarchiver *unArchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:mData1];
Person *person1 = [unArchiver decodeObjectForKey:@"girlFriend"];
NSLog(@"%@", person1);
//归档 与 反归档
//多用于自定义数据类型, 比如Person, 并且能够进行归档的数据类型, 必须遵守, 实现编码和解码的方法, 对属性进行编码和解码, 编码和解码的key值必须相同
}
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