参考文章：
沙盒(sandbox)（官方文档 ）
iOS沙盒主要包含以下三个文件夹：
获取沙盒路径
1 2 NSString *homeDir = NSHomeDirectory ();
注:每次编译代码会生成新的沙盒,注意是编译不是启动,所以模拟器或者真机运行你每次运行所得到的沙盒路径都是不一样,就是上面提到的标识符不一样,正式版app真机的话启动杀死,不会生成新的沙盒
1)、Documents
保存应用程序运行时生成的需要持久化数据，iTunes会自动备份该目录。
1 2 NSString *docPath = [NSSearchPathForDirectoriesInDomains (NSDocumentDirectory , NSUserDomainMask , YES ) lastObject];
2)、Library
存储程序的默认设置和其他状态信息，iTunes会自动备份该文件目录
Library/Caches：存放缓存文件，iTunes不会备份此目录，此目录下文件不会在应用退出时删除，通常存放体积比较大，但并不是很重要的资源
Library/Preferences：保存应用的所有偏好设置，iOS的Setting（设置）应用会在该目录中查找应用的设置信息，iTunes会自动备份该目录。
包含两个文件夹
1 2 3 4 5 6 7 8 9 NSString *libDir = [NSSearchPathForDirectoriesInDomains (NSLibraryDirectory , NSUserDomainMask , YES ) lastObject];NSString *cachePath = [NSSearchPathForDirectoriesInDomains (NSCachesDirectory , NSUserDomainMask , YES ) lastObject];NSString *prePath = [NSSearchPathForDirectoriesInDomains (NSPreferencePanesDirectory , NSUserDomainMask , YES ) lastObject];
3)、tmp
保存应用程序运行时所需的临时数据，使用完毕后再将相应的文件从该目录删除，应用没有运行时，系统也有可能会清除该目录下的文件，iTunes不会同步该目录，你的iPhone重启时，该目录下的文件会被删除。
数据存储的几种方式 1)、property list（属性列表）
只能存储系统自带的数据类型，一般实际开发中存储字典、数组，自定义的模型无法进行存储。
1 2 3 4 5 6 7 8 9 #define kUserPath [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject stringByAppendingPathComponent:@"local.plist" ] NSMutableDictionary *dic = [NSMutableDictionary dictionary]; [dic setObject:@"小明" forKey:@"name" ]; [dic writeToFile:kUserPath atomically:YES ]; NSMutableDictionary *localDic = [[NSMutableDictionary alloc] initWithContentsOfFile:kUserPath]; NSLog (@"localDic = %@" ,localDic);
2)、Preference（偏好设置）:NSUserDefaults
只能存储系统自带的数据类型，自定义的对象无法存储。
1 2 3 4 5 6 7 8 9 NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];[userDefaults setObject:@"123" forKey:@"account" ]; [userDefaults setObject:@"123456" forKey:@"pwd" ]; [userDefaults setBool:YES forKey:@"status" ]; [userDefaults synchronize];
3)、文件读写 3.1 简单对象写入文件 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 NSArray *array = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory , NSUserDomainMask , YES ); NSString *docPathStr = [array lastObject]; NSString *strPath = [docPathStr stringByAppendingPathComponent:@"/text.txt" ]; NSString *contant = @"Hello, world!" ; [contant writeToFile:strPath atomically:YES encoding:NSUTF8StringEncoding error:nil ]; NSString *arrayPath = [docPathStr stringByAppendingString:@"/arry.txt" ]; NSArray *arr = @[ @"Jobs" , @"Cook" , @"Apple" ]; [arr writeToFile:arrayPath atomically:YES ]; NSString *dicPath = [docPathStr stringByAppendingString:@"/dic.txt" ]; NSDictionary *dic = @{ @"name" : @"Jobs" , @"sex" : @"男" }; [dic writeToFile:dicPath atomically:YES ]; UIImage *img = [UIImage imageNamed:@"avatar1" ]; NSString *dataPath = [docPathStr stringByAppendingPathComponent:@"data.txt" ]; NSData *data = UIImagePNGRepresentation (img); [data writeToFile:dataPath atomically:YES ]; #pragma mark - NSFileManager NSError *error; NSFileManager *manger = [NSFileManager defaultManager]; NSString *filePath = [docPathStr stringByAppendingString:@"/test1" ]; [manger createDirectoryAtPath:filePath withIntermediateDirectories:YES attributes:nil error:nil ]; NSString *filePath1 = [filePath stringByAppendingString:@"/test.png" ]; [manger createFileAtPath:filePath1 contents:data attributes:nil ]; NSString *filePath2 = [docPathStr stringByAppendingString:@"/test1/test2.png" ]; [manger copyItemAtPath:filePath1 toPath:filePath2 error:&error]; NSString *filePath3 = [docPathStr stringByAppendingString:@"/test2" ]; [manger createDirectoryAtPath:filePath3 withIntermediateDirectories:YES attributes:nil error:&error]; NSString *filePath4 = [filePath3 stringByAppendingString:@"/test4.png" ]; [manger moveItemAtPath:filePath1 toPath:filePath4 error:&error]; [manger removeItemAtPath:filePath4 error:&error]; BOOL isExist = [manger fileExistsAtPath:filePath4]; NSLog (@"isExist = %d" ,isExist); NSArray *fileArr = [manger subpathsOfDirectoryAtPath: docPathStr error:nil ]; NSLog (@"fileArr = %@" ,fileArr); NSArray *fileArr2 = [manger subpathsAtPath: docPathStr ]; NSLog (@"fileArr2 = %@" ,fileArr2);
3.2、NSKeyedArchiver（归档）+ 文件读写
该方式一般都是保存自定义对象的时候使用.因为plist文件不能够保存自定义对象.
复杂对象写入文件的过程（复杂对象->归档->NSData->writeToFile）
从文件中读取出复杂对象过程（读取文件->NSData->反归档->复杂对象）
首先，复杂对象所属的类要遵守
其次，实现协议中的两个方法：
-(void)encodeWithCoder:(NSCoder *)aCoder; //序列化
-(id)initWithCoder:(NSCoder *)aDecoder; //反序列化
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 @interface UserModel : NSObject <NSCoding >@property (nonatomic , assign ) int ID;@property (nonatomic ,copy )NSString *name;@property (nonatomic ,copy )NSString *pwd;@property (nonatomic ,assign )int age;@end - (instancetype )initWithCoder:(NSCoder *)aDecoder{ self = [super init]; if (self ) { self .ID = [aDecoder decodeIntForKey:@"ID" ]; self .name = [aDecoder decodeObjectForKey:@"name" ]; self .pwd = [aDecoder decodeObjectForKey:@"pwd" ]; self .age = [aDecoder decodeIntForKey:@"age" ]; } return self ; } - (void )encodeWithCoder:(NSCoder *)aCoder{ [aCoder encodeInt:self .ID forKey:@"ID" ]; [aCoder encodeObject:self .name forKey:@"name" ]; [aCoder encodeObject:self .pwd forKey:@"pwd" ]; [aCoder encodeInt:self .age forKey:@"age" ]; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 UserModel *userModel = [[UserModel alloc] init]; userModel.ID = 10 ; userModel.name = @"Jobs" ; userModel.pwd = @"123456" ; userModel.age = 26 ; NSMutableData *data = [NSMutableData data];NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:data];[archiver encodeObject:userModel forKey:@"user" ]; [archiver finishEncoding]; NSString *mulDataPath = [NSSearchPathForDirectoriesInDomains (NSDocumentDirectory , NSUserDomainMask , YES ) lastObject];NSString *dataPath = [mulDataPath stringByAppendingString:@"/archiver.plist" ];[data writeToFile:dataPath atomically:YES ]; NSData *readData = [NSData dataWithContentsOfFile:dataPath];NSKeyedUnarchiver *unAchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:readData];UserModel *localUser1 = [unAchiver decodeObjectForKey:@"user" ]; [unAchiver finishDecoding];
注：归档不是数据持久化手段，而是为文件读写做准备。文件读写才是数据持久化的方式。
Office等文件预览 方法一：UIDocumentInteractionController 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 - (void )readDocWithDucument1 { NSString *ducumentLocation = [[NSBundle mainBundle] pathForResource:docNameString ofType:docTypeString]; NSURL *url = [NSURL fileURLWithPath:ducumentLocation]; NSString *cachePath = [NSSearchPathForDirectoriesInDomains (NSCachesDirectory , NSUserDomainMask , YES ) lastObject]; cachePath = [cachePath stringByAppendingPathComponent:@"temp.docx" ]; NSURL *cacheUrl = [NSURL fileURLWithPath:cachePath]; NSFileManager *fileManger = [NSFileManager defaultManager]; NSError *error = nil ; [fileManger copyItemAtURL:url toURL:cacheUrl error:&error]; _documentInteractionController = [UIDocumentInteractionController interactionControllerWithURL:cacheUrl]; _documentInteractionController.delegate = self ; [_documentInteractionController presentOptionsMenuFromRect:CGRectZero inView:self .view animated:YES ]; } - (UIViewController *)documentInteractionControllerViewControllerForPreview:(UIDocumentInteractionController *)controller { return self ; } - (UIView *)documentInteractionControllerViewForPreview:(UIDocumentInteractionController *)controller { return self .view; } - (CGRect )documentInteractionControllerRectForPreview:(UIDocumentInteractionController *)controller { return self .view.bounds; }
方法二：QLPreviewController 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 - (void )quickLook { QLPreviewController *preVC = [[QLPreviewController alloc] init]; preVC.dataSource = self ; [self presentViewController:preVC animated:YES completion:nil ]; } #pragma mark - QLPreviewControllerDataSource 代理方法 - (NSInteger )numberOfPreviewItemsInPreviewController:(QLPreviewController *)controller { return 1 ; } - (id <QLPreviewItem>)previewController:(QLPreviewController *)controller previewItemAtIndex:(NSInteger )index { NSString *ducumentLocation = [[NSBundle mainBundle] pathForResource:docNameString ofType:docTypeString]; NSURL *url = [NSURL fileURLWithPath:ducumentLocation]; return url; }
方法三：UIWebView 1 2 3 4 5 6 7 8 9 10 11 12 13 14 - (void )readDocfile { NSString *ducumentLocation = [[NSBundle mainBundle] pathForResource:docNameString ofType:docTypeString]; NSURL *url = [NSURL fileURLWithPath:ducumentLocation]; UIWebView *webView = [[UIWebView alloc] initWithFrame:self .view.frame]; webView.delegate = self ; webView.multipleTouchEnabled = YES ; webView.scalesPageToFit = YES ; NSURLRequest *request = [NSURLRequest requestWithURL:url]; [webView loadRequest:request]; [self .view addSubview:webView]; }
