iOS数据持久化

1 NSArray *array = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,NO);// NSUserDomainMask 代表从用户文件夹下面找
2 NSString *documents = [array objectAtIndex:0];
3 // 在iOS中只会有一个目录跟传入的这个参数相匹配，里面只有一个元素

// 1. 创建一个可变字典对象
NSMutableDictionary *dict = [NSMutableDictionary dictionary];
// 2. 将要存入的数据封装成为字典
[ dict setObject:@"张三" forKey:@"name" ];
[ dict setObject:@"男" forKey:@"性别"];
[ dict setObject:@"23" forKey:@"age" ];
[ dict setObject:@"2525252525" forKey:@"QQ"];
// 3. 将字典写入到plist文件中
[dict WriteToFile:path atomically:YES];

NSDictionary *dict = [NSDictionary dictionaryWithContentsOfFile:path];
NSLog(@"name:%@",[dict objectForKey:@"name"]);
NSLog(@"性别:%@",[dict objectForKey:@"性别"]);
NSLog(@"age:%@",[dict objectForKey:@"age"]);
NSLog(@"QQ:%@",[dict objectForKey]);

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:@"张三" forKey:@"name"];
[defaults setObject:@"123456" forKey:@"pwd"];
[defaults setFloat:17.0f  forKey:@"text_size"];
[defaults setBool:YES  forKey:@"auto_login"];

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *name = [defaults stringForKey:@"name"];
NSString *pwd  =  [defaults stringForKey:@"pwd"];
float textSize = [defaults floatForKey:@"text_size"];
Bool autoLogin = [defaults boolForKey:@"auto_login"];

NSArray *array = [NSArray arrayWithObjects:@"a",@"b",@"c",nil];
[NSKeyedArchiver archiverRootObject:array toFile:path];

NSArray *array = [NSKeyedUnarchiver unarchiveObjectWithFile:path];

Student.h

@interface Student:NSObject<NSCoding>
@property (nonatomic,copy) NSString *name;
@property (nonatomic,assign) int id;
@property (nonatomic,assign) int age;
@property (nonatomic,assign) int score;
@property (nonatomic,assign) float height;
@end

@implementation Student
- (void)encodeWithCoder:(NSCoder *)encoder
{
      [encoder encodeObject:self.name    forKey:@"name"];
      [encoder encodeObject:self.id         forKey:@"id"];
      [encoder encodeObject:self.age      forKey:@"age"];
      [encoder encodeObject:self.score    forKey:@"score"];
      [encoder encodeObject:self.height   forKey:@"height"];
}
- (id)initWithCoder:(NSCoder *)decoder
{
     self.name = [decoder decodeObjectForKey:@"name"];
     self.id       = [decoder decodeObjectForKey:@"id"];
     self.age    = [decoder decoderObjectForKey:@"age"];
     self.score  = [decoder decoderObjectForKey:@"score"];
     self.height = [decoder decoderObjectForKey:@"height"];
}
@end

Student *stu = [Student alloc] init];
stu.name = @"张三";
stu.id       = 11;
stu.age     = 23;
stu.score   = 99;
stu.height = 1.70f;
[NSKeyedArchiver archiveRootObject:student  toFile:path];

Student *stu = [NSKeyedUnArchiver unarchiveObjectWithFile:path];

// 1. 新建一块可变的数据存储空间
NSMutableData *data = [NSMutableData data];
// 2.将数据存储空间与一个NSKeyedArchiver对象
NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:data];
// 3. 开始归档对象，归档的数据会存储到NSMutableData中
[archiver encodeObject:student1 forKey:@"student1"];
[archiver encodeObject:student2 forKey:@"student2"];
[archiver encodeObject:student3 forKey:@"student3"];
// 4. 归档完毕调用
[archiver finishEncoding];
// 5. 将存储的数据写入到文件
[data writeToFile:path atomically:YES];

// 1. 从文件中读取数据
NSData *data = [NSData dataWithContentsOfFile:path];
// 2. 根据数据，解析成为NSKeyedUnarchiver对象
NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:data];
Student *student1 = [unarchiver decodeObjectForKey:@"student1"];
Student *student2 = [unarchiver decodeObjectForKey:@"student2"];
Student (student3 =  [unarchiver decodeObjectForKey:@"student3"];
// 3. 恢复完毕
[unarchiver finishDecoding];

// 1. 临时存储student1的数据
NSData *data = [NSKeyedArchiver archivedDataWithRootObject:student1];
// 2. 解析data ,生成一个新的student对象
Student *student2 = [NSKeyedUnArchiver unarchiveObjectWithData:data];
// 3. 分别打印内存地址
NSLog(@"student1:0X%p",student1);
NSLog(@"student2:0X%p",student2);

create table t_student(name text,age integer); 

NSString *path = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES) lastObject ];
NSString *sqlFilePath = [path stringByAppendingPathComponent:@"student.sqlite"];

int result = sqlite3_open(sqliteFilePath.UTF8String,&_db);
// 上面传入的参数告诉系统数据库文件的地址,获取到数据库之后保存到什么地方

if(result ==SQLite_OK){
       NSLog(@"打开数据库成功");
}

sqlite3_close(db);

NSString *sql = @"create table if not exists t_student(name text,age integer ,score real,id integer primary key auto increment);"
result = sqlite3_exec(_db,sql.UTF8String,NULL,NULL,NULL);
// 第1个参数为需要执行sql 语句的数据库，第2个参数为要执行的sql语句，第3个参数为执行成功的回调，第4个参数为回调的参数，第5个为错误信息

NSString *sql = @"insert into t_student(name,age,height) values(‘张三‘，23，170);";
int result = sqlite3_exec(_db,sql.UTF8String,NULL,NULL,NULL);
if(result == SQLIKE_OK){
     NSLog(@"插入数据成功");
}else{
    NSLog(@"插入数据失败");
}

NSString *sql = @"insert into t_student(name,age) values(？,？);";
sqlite3_stmt *stmt;
if(sqlite3_prepare_v2(_db,sql,-1,&stmt,NULL) == SQLITE_OK)
{// 返回SQLITE_OK 说明SQL语句准备成功
   sqlite3_bind_text(stmt,1,‘张三‘，NULL)；
   sqlite3_bind_int(stmt,2,27);    
}
  if(sqlite3_step(stmt) != SQLITE_DONE){
    NSLog(@"插入数据错误");
}
sqlite3_finalize(stmt);

// 1. 准备查询
sqlite3_stmt *stmt;
// 提取数据的对象
int result = sqlite3_prepare_v2(_db,sql.UTF8String,-1,&stmt,NULL);
// 2. 开始查询
if (result == SQLITE_OK)
{
    NSLog(@"准备成功");
    // 3.调用sqlite3_step方法
    while(sqlite3_step(stmt) == SQLITE_ROW)
     {// 返回SQLITE_ROW代表遍历到一条新的记录
         NSLog(@"成功提取了一条数据");
         const unsigned char * name = sqlite3_column_text(stmt,0);
         double score = sqlite3_column_double(stmt,1);
         int rank = sqlite3_column_int(stmt,2);
         NSLog(@"%s %.f %d",name,score,rank);
     }
}else{
    NSLog(@"准备失败");
}
// sqlite3_step()返回的SQLITE_ROW代表遍历到一条新的记录
// sqlite3_column_*() 用于获取每个字段对应的值，第2个参数是字段的索引，从0开始

 [self.dbQueue inDatabase:^(FMDatabase *db) {
        if ([db executeQuery:@"INSERT INTO  t_student (name, socre, rank) VALUES(?, ?, ?);", @"jack", @(99.8), @(1)]))
         {
             NSLog(@"插入表成功");
         }else{
             NSLog(@"插入表失败");
        }
    }];

// 加载数据库
self.db = [FMDatabaseQueue databaseQueueWithPath:sqlitePath];

// 更新数据库
- (IBAction)update:(UIButton *)sender{
      [self.dbQueue inTransaction:^(FMDatabase *db, BOOL *rollback) {
        // 提交事务
        [db  beginTransaction];
        if ([db executeUpdate:@"update t_student set mongy = 1000 where name = ‘张三‘;"]) {
            NSLog(@"张三");
        }
        // 意外中断
        NSArray *arr = @[@"abc"];
        arr[6];
        if ([db executeUpdate:@"update t_student set money = 2000 where name =‘王五‘;"]) {
            NSLog(@"王五");
        }
        NSLog(@"%s",__func__);
        /** 提交事务 */
        [db commit];
    }];
}

// 实例化数据模型
NSURL *modelURL = [[NSBundle mainBundle] URLForResource:modelName withExtension:@"momd"];
NSManagedObjectModel *model = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
// 实例化持久化存储
NSPersistentStoreCoordinator *psc = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model];
NSURL *dbURL = [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
dbURL = [dbURL URLByAppendingPathComponent:dbName];
[psc addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:dbURL options:nil error:NULL];
// 实例化上下文
_managedObjectContext = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSMainQueueConcurrencyType];
[_managedObjectContext setPersistentStoreCoordinator:psc];

// 1. 从应用程序包开始加载模型文件
NSManageObjectModel *model = [NSManageObjectModel mergedModelFromBundles:nil];
// 2. 传模型，初始化NSPersistentStoreCoordinator
NSPersistentStoreCoordinator *psc = [[[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model]；
// 3. SQL的文件路径
NSString *docs = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES) lastObject];
NSURL *url = [NSURL fileURLWithPath:[docs stringByAppendingPathComponent:@"person.data"]];
// 4. 添加持久化存储库,这里使用SQLite作为存储库
NSError *error = nil;
NSPersistentStore *store = [psc addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:url options:nil error:&error ];
if(store == nil){ // 直接抛异常
   NSException raise:@"添加数据库错误" format:@"%@",[error localizedDescription]];
}
// 5. 初始化上下文，设置persistentStoreCoordinator 属性
NSManagedObjectContext *context = [[NSManagedObjectContext alloc] init ];
context.persistentStoreCoordinator = psc;

// 传入上下文，创建一个person实体对象
NSManagedObject *person = [NSEntityDescription insertNewObjectForEntityForName:@"Person" inManagedObjectContext:context];
// 设置简单属性
[person setValue:@"张三" forKey:@"name"];
[person setValue:[NSNumber numberWithInt:27] forKey:@"age"];
// 传入上下文, 创建一个Card实体对象
NSManagedObject *card = [NSEntityDescription insertNewObjectForEntityForName:@"Card" inManagedObjectContext:context];
// 设置card的简单属性
[card setValue:@"23321321313" forKey:@"no"];
// 设置person与card之间的关联关系
[person setValue:@"card" forKey:@"card"];
// 利用上下文对象，将数据同步到持久化存储库
NSError *error = nil;
BOOL success = [context save:&error];
if (!success){
    [NSException raise:@"访问数据库错误" format:@"%@",[error localizedDescription]];
}// 如果只是想做更新操作，只需要在更改了实体对象的属性后调用[context save:&error],就可以将更改的数据同步数据库.

// 初始化一个查询请求
NSFetchRequest *request = [NSFetchRequest alloc] init];
// 设置要查询的实体
NSEntityDescription *desc = [NSEntityDescription entityForName:@"Person" inManagedObjectContext:context]; 
// 设置排序(age降序)
NSSortDescriptor *sort = [NSSortDescriptor sortDescriptorWithKey:@"age" ascending:NO ];
request.sortDescriptors = [NSArray arrayWithObject:sort];
// 设置条件过滤
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name like%@",@"*aaaaa*"];
request.predicate = predicate;
// 对于条件过滤，数据库中的％ 要使用＊代替

// 执行请求
NSError *error = nil;
NSArray *objs = [context executeFetchRequest:request error:&error];
if (error){
    [NSException raise:@"查询错误" format:@"%@",[error localizedDescription]];
}
// 遍历数据
for (NSManagedObject *obj  in objs){
    NSLog(@"name = %@",[obj valueForKey:@"name"]);
}

// 传入需要删除的实体对象
[context deleteObject:managedObject];
// 将结果同步到数据库
NSError *error = nil;
[context save:&error];
if (error){
    [NSException raise :@"删除错误" format:@"%@",[error localizedDescription]];
}

// 生成person实体对象
Person *person = [NSEntityDescription insertNewObjectForEntityForName:@"Person"   inManagedObjectContext:context];
person.name = @"张三";
person.age = [NSNumber numberWithInt:27];
Card *card = [NSEntityDescription insertNewObjectForEntityForName:@"Card" inManagedObjectContext:context];
card.no = @"23423422342";
person.card = card;