IOS数据持久化之归档NSKeyedArchiver, NSUserDefaults,writeToFile
//2.文件读写
//支持:NSString, NSArray , NSDictionay, NSData
//注:集合(NSArray, NSDictionay)中得元素也必须是这四种类型, 才能够进行文件读写
//string文件读写
NSString *string = @"假如给我有索纳塔";
//Document
NSString *docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
//指定文件路径 aaa.txt
NSString *filePath = [docPath stringByAppendingPathComponent:@"aaa.txt"];
NSLog(@"**%@", filePath);
//写入文件
//参数1:文件路径, 如果文件路径下没有此文件, 系统会自动创建一个文件.
//参数2:是否使用辅助文件
//参数3:编码格式
//参数4:错误
NSError *error = nil;
BOOL result = [string writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:&error];
if (result) {
NSLog(@"写入成功");
} else {
NSLog(@"写入错误");
}
if (error) {
NSLog(@"出现错误");
}
//取值操作,
NSError *error1 = nil;
NSString *contenSring = [[NSString alloc] initWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:&error1];
if (error1) {
NSLog(@"error:%@", error1);
} else {
NSLog(@"文件内容%@", contenSring);
}
[contenSring release];
//NSArray的文件读写
NSArray *array = @[@"123", @"abc", @"apm"];
//写入操作, 格式XML
//Library, test.txt
//library路径
NSString *libraryPath1 = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) firstObject];
//文件路径
NSString *textPath = [libraryPath1 stringByAppendingPathComponent:@"text.txt"];
NSLog(@"%@", textPath);
//写入
BOOL result4 = [array writeToFile:textPath atomically:YES];
//判断是否写入成功
if (result4) {
NSLog(@"写入成功");
} else {
NSLog(@"写入失败");
}
//取值操作
NSArray *bbb = [[NSArray alloc] initWithContentsOfFile:textPath];
NSLog(@"%@", bbb);
[bbb release];
//NSDictionary, 格式:XMl
NSDictionary *dic = @{@"a": @"aaa", @"1": @"111", @"*" :@"**"};
//Caches, dic.txt
//Caches文件路径
NSString *cachesPath1 = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES)firstObject];
//dic.txt路径
NSString *dicPath = [cachesPath1 stringByAppendingPathComponent:@"dic.txt"];
NSLog(@"%@", dicPath);
//写入
BOOL result3 = [dic writeToFile:dicPath atomically:YES];
//判断写入是否成功
if (result3) {
NSLog(@"写入成功");
} else {
NSLog(@"写入shib");
}
//取值操作
NSDictionary *dict = [[NSDictionary alloc] initWithContentsOfFile:dicPath];
NSLog(@"%@", dict);
[dict release];
//NSData NSString *tmpPath = NSTemporaryDirectory();
NSString *string2 = @"132456789";
//字符串转data
NSData *data = [string2 dataUsingEncoding:NSUTF8StringEncoding];
//tmp路径
//tmp data.txt
NSString *tmpPath1 = NSTemporaryDirectory();
//data.txt路径
NSString *dataPath = [tmpPath1 stringByAppendingPathComponent:@"data.txt"];
//写入
BOOL result1 = [data writeToFile:dataPath atomically:YES];
//判断是否写入成功
if (result1) {
NSLog(@"写入成功");
} else {
NSLog(@"写入失败");
}
//取值
NSData *datat = [[NSData alloc] initWithContentsOfFile:dataPath];
NSString *dataSting = [[NSString alloc] initWithData:datat encoding:NSUTF8StringEncoding];
[datat release];
NSLog(@"%@", dataSting);
[dataSting release];
1 //3.归档 / 反归档 2 //归档的实质:把其他类型数据(比如:Person),先转化成NSData, 再写入文件 3 //能进行归档的对象, 必须遵守<NSCoding> 4 5 //归档 6 Person *person = [[[Person alloc] init] autorelease]; 7 person.name = @"辉哥"; 8 person.age = @"18"; 9 person.gender = @"男"; 10 //NSLog(@"%@", person); 11 12 13 //可变data 14 NSMutableData *mData = [[NSMutableData alloc] initWithCapacity:0]; 15 16 //NSKeyedArchiver, 压缩工具, 继承于NSCoder,主要用于编码 17 NSKeyedArchiver *archiver= [[NSKeyedArchiver alloc] initForWritingWithMutableData:mData]; 18 //把Person对象压到Data中 19 [archiver encodeObject:person forKey:@"girlFriend"]; 20 //完成压缩 21 [archiver finishEncoding]; 22 [archiver release]; 23 NSLog(@"%@", mData); 24 25 //主目录中, person.txt 26 NSString *homePatha = NSHomeDirectory(); 27 NSString *mDataPath = [homePatha stringByAppendingPathComponent:@"person.txt"]; 28 NSLog(@"%@", mDataPath); 29 BOOL result = [mData writeToFile:mDataPath atomically:YES]; 30 if (result) { 31 NSLog(@"写入成功"); 32 } else { 33 NSLog(@"写入失败"); 34 } 35 [mData release]; 36 37 //反归档 38 NSData *contentData = [[NSData alloc] initWithContentsOfFile:mDataPath]; 39 //NSKeyedUnarchiver解压工具, 继承于NSCoder 40 NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:contentData]; 41 [contentData release]; 42 //通过key找到person 43 Person *contentPerson = [unarchiver decodeObjectForKey:@"girlFriend"]; 44 NSLog(@"gd%@", contentPerson); 45 [unarchiver release]; 46
1 2 //数据持久化:数据永久的保存 3 //数据持久化的实质:把数据写入文件, 再把文件存到硬盘 4 //IOS沙盒机制:IOS系统为每个app生成一个文件夹(沙盒), 这个文件夹只允许当前的APP访问 5 //沙盒的主目录 6 //沙盒主目录的文件夹名字由 十六进制数 和 - 组成, 保证沙盒安全性 7 //NSHomeDirectory() 8 NSString *homePath = NSHomeDirectory(); 9 NSLog(@"%@", homePath); 10 11 //Documents文件 12 //存放着一些比较重要的用户信息, 比如游戏的存档 13 //Documents中得文件会被备份 或者 存入iCloud 中, 所以存到documents中得文件不能过大, 如果过大, 会在应用审核过程中遭到拒审 14 //参数1:文件夹名称 15 //参数2:搜素域 优先级user>local>network>system 16 //参数3:相对路径或者绝对路径, yes 是绝对, no是相对 17 //因为相同文件名的文件可能有多个, 所以返回的是一个数组 18 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 19 //NSLog(@"%@", paths); 20 21 NSString *docmentsPath = [paths firstObject]; 22 //NSLog(@"%@", docmentsPath); 23 24 //Library,资源库 存放一些不太重要, 相对比较大得文件 25 NSString *libraryPath = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) firstObject]; 26 //NSLog(@"libraryPath:%@", libraryPath); 27 //Library/Caches, 缓存, 网页缓存, 图片缓存, 应用中得"清理缓存"功能, 就是清理这个文件夹下得内容 28 NSString *cachesPath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) firstObject]; 29 //NSLog(@"%@", cachesPath); 30 //LanunchImages, 由LaunchScreen.xib生成的启动图片 31 32 33 //Library/Preferences, 偏好设置, 存放用户对这个应用的设置或配置 34 //注:路径找不到,通过NSUserDefaults访问 35 36 37 //tmp, 临时文件, 存放下载的压缩包, 解压过后删除 38 NSString *tmpPath = NSTemporaryDirectory(); 39 NSLog(@"%@", tmpPath); 40 41 // *.app, 包,用右键,显示包内容, 查看里面存放的文件 42 //IOS8.0以后, *.app单独存放到一个文件内 43 // *.app中这个文件,只能够访问,不能够修改(写入) 44 NSString *bundlePath = [[NSBundle mainBundle] bundlePath]; 45 NSLog(@"***%@", bundlePath); 46 47 48 //NSFileManager文件管理工具, 主要用于添加, 移动, 修改, 拷贝文件, 继承于NSObject 49 //文件管理工具是个单例 50 NSFileManager *fm = [NSFileManager defaultManager]; 51 //文件路径 52 NSString *hPath = [[fm URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] firstObject]; 53 NSLog(@"hPath:%@", hPath); 54 55 //创建文件夹, 56 //在主目录中创建images文件夹 57 NSString *mainPath = NSHomeDirectory(); 58 NSString *directoryPath = [mainPath stringByAppendingPathComponent:@"images"]; 59 NSLog(@"%@", directoryPath); 60 61 NSError *error = nil; 62 //attributes设置文件夹的属性,读写,隐藏等等 63 //NSDictionary *attributes = @{NSFileAppendOnly: @YES}; 64 BOOL result = [fm createDirectoryAtPath:directoryPath withIntermediateDirectories:YES attributes:nil error:&error]; 65 if (result) { 66 NSLog(@"创建成功"); 67 } else { 68 69 NSLog(@"创建失败"); 70 } 71 72 //创建文件 73 //在Images文件夹中创建image.png 74 NSString *imagePath = [directoryPath stringByAppendingPathComponent:@"image.png"]; 75 NSLog(@"%@", imagePath); 76 77 //找图片 78 NSString *meinvPath = [[NSBundle mainBundle] pathForResource:@"美女7" ofType:@"png"]; 79 NSData *imageData = [NSData dataWithContentsOfFile:meinvPath]; 80 81 //创建图片 82 BOOL result2 = [fm createFileAtPath:imagePath contents:imageData attributes:nil]; 83 if (result2) { 84 NSLog(@"创建成功"); 85 } else { 86 NSLog(@"创建失败"); 87 } 88 89 //判断文件是否存在 90 if ([fm fileExistsAtPath:imagePath]) { 91 NSLog(@"存在"); 92 //删除 93 NSError *error = nil; 94 BOOL result = [fm removeItemAtPath:imagePath error:&error]; 95 if (result) { 96 NSLog(@"删除成功"); 97 } else { 98 NSLog(@"删除失败%@", error); 99 } 100 } 101 102 NSString *path = NSHomeDirectory(); 103 NSString *filePath = [path stringByAppendingPathComponent:@"aaa.txt"]; 104 NSLog(@"1*%@", filePath); 105 NSString *filePath1 =[path stringByAppendingString:@".aaa.txt"]; 106 NSLog(@"2*%@", filePath1); 107 NSString *filePath2 = [path stringByAppendingFormat:@"/baa.txt"]; 108 NSLog(@"3*%@", filePath2); 109 NSString *filePath3 = [path stringByAppendingPathExtension:@"caaa.txt"]; 110 NSLog(@"4*%@", filePath3); 111 112 113 114 115 116 117 //数据持久化的方式 118 //1. NSUserDefaults, 继承于NSObject, 单例设计模式, 内部存值用的KVC 119 NSInteger money = 100000; 120 money -= 99999; 121 122 //存数据, 存放到PreFerences文件夹内的*.plist文件中, 以字典的形式存储 123 NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults]; 124 125 [userDefaults setInteger:1 forKey:@"myMoney"]; 126 //同步操作, 让存入的数据写入文件 127 [userDefaults synchronize]; 128 129 130 //取数据, key和存数据的key保持一致 131 NSUserDefaults *user = [NSUserDefaults standardUserDefaults]; 132 NSInteger myMoney = [user integerForKey:@"myMoney"]; 133 NSLog(@"%ld", myMoney); 134 135 136 NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults]; 137 NSInteger mmoney = [defaults integerForKey:@"myLifeMoney"]; 138 if (mmoney <= 10) { 139 NSLog(@"不能花了"); 140 } else { 141 NSLog(@"花了10, 吃了俩"); 142 mmoney -= 10; 143 [defaults setInteger:mmoney forKey:@"myLifeMoney"]; 144 [defaults synchronize]; 145 } 146 147 148 //NSUserDefaults, 支持的数据类型:array, dictionary, string, data, date, number, bool 149 //NSUserDefaults, 一般存一些数值, 不存大量的数据 150 //是不是第一次启动 151 NSUserDefaults *userDefault1 = [NSUserDefaults standardUserDefaults]; 152 BOOL isFirst = [userDefault1 boolForKey:@"isFirst"]; 153 if (isFirst == NO) { 154 NSLog(@"第一次启动"); 155 [userDefault1 setBool:YES forKey:@"isFirst"]; 156 } else { 157 NSLog(@"不是第一次启动"); 158 }
Person.h 中实现NSCoding协议
#import <Foundation/Foundation.h> @interface Person : NSObject<NSCoding> @property (nonatomic , retain) NSString *name, *age, *gender; @end
Person.m 中实现的方法
1 #import "Person.h" 2 3 @implementation Person 4 - (void)dealloc 5 { 6 [_age release]; 7 [_name release]; 8 [_gender release]; 9 [super dealloc]; 10 11 } 12 13 - (NSString *)description 14 { 15 return [NSString stringWithFormat:@"name:%@, age:%@, gender:%@", _name, _age, _gender]; 16 } 17 18 #pragma mark - NSCoding 19 - (void)encodeWithCoder:(NSCoder *)aCoder { 20 //编码 21 [aCoder encodeObject:self.name forKey:@"NAME"]; 22 [aCoder encodeObject:self.age forKey:@"AGE"]; 23 [aCoder encodeObject:self.gender forKey:@"GENDER"]; 24 } 25 - (id)initWithCoder:(NSCoder *)aDecoder { 26 self = [super init]; 27 if (self) { 28 //解码 29 self.name = [aDecoder decodeObjectForKey:@"NAME"]; 30 self.age = [aDecoder decodeObjectForKey:@"AGE"]; 31 self.gender = [aDecoder decodeObjectForKey:@"GENDER"]; 32 } 33 return self; 34 } 35 36 37 @end
@interface Person : NSObject<NSCoding>
