1> XML属性列表归档:.plist
2> 偏好设置:NSUserDefault
3> 归档:NSKeydeArchiver
4> 关系型数据库:Sqlite 3
5> 对象型的数据库:Core Data
沙盒:文件系统目录,iOS应用程序都是独立的沙盒;
Documents: 如:数据库文件放置这里;
Library: Caches, Preferences 如:图片等缓冲文件放置这里,会自动删除掉的空间;
tmp:
推介工具软件:SimPholders
- (void)initWithOther
{
// 根目录
NSString *home = NSHomeDirectory();
NSLog(@"home : %@", home);
// 获取Document,创建一个bank.plist文件
NSString *document = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
NSString *filePath = [document stringByAppendingPathComponent:@"bank.plist"];
NSLog(@"filePath : %@", filePath);
// 字典写入
NSDictionary *dic = @{@"name" : @"yulong", @"count" : @"6", @"id" : @"123456", @"type" : @"农行"};
[dic writeToFile:filePath atomically:YES];
// 读文件
NSDictionary *readDic = [NSDictionary dictionaryWithContentsOfFile:filePath];
NSLog(@"readDic : %@", readDic);
}
- (void)writeData
{
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:@"yulong" forKey:@"name"];
[defaults setInteger:1 forKey:@"money"];
[defaults setDouble:1.78 forKey:@"height"];
[defaults synchronize];
}
- (void)readData
{
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *name = [defaults objectForKey:@"name"];
NSUInteger money = [defaults integerForKey:@"money"];
double height = [defaults doubleForKey:@"height"];
NSLog(@"name : %@, money : %lu, height : %f", name, (unsigned long)money, height);
}
偏好设置:保存应用程序的配置信息;
- (void)writeArchive
{
Student *student = [[Student alloc] init];
student.name = @"yulong";
student.age = 8;
student.className = @"小班一班";
student.classID = @"1234560798";
NSString *document = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
NSString *filePath = [document stringByAppendingPathComponent:@"student.txt"];
NSLog(@"filePath : %@", filePath);
[NSKeyedArchiver archiveRootObject:student toFile:filePath];
}
- (void)readArchive
{
NSString *document = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
NSString *filePath = [document stringByAppendingPathComponent:@"student.txt"];
NSLog(@"filePath : %@", filePath);
Student *student = [NSKeyedUnarchiver unarchiveObjectWithFile:filePath];
NSLog(@"%@ %lu %@ %@", student.name, (unsigned long)student.age, student.className, student.classID);
}
自定义对象保存到文件中,必须实现
- (instancetype)initWithCoder:(NSCoder *)aDecoder
{
NSLog(@"%s", __func__);
self = [super init];
if (self)
{
_name = [aDecoder decodeObjectForKey:@"name"];
_age = [aDecoder decodeIntegerForKey:@"age"];
_className = [aDecoder decodeObjectForKey:@"className"];
_classID = [aDecoder decodeObjectForKey:@"classID"];
}
return self;
}
- (void)encodeWithCoder:(NSCoder *)aCoder
{
NSLog(@"%s", __func__);
[aCoder encodeObject:_name forKey:@"name"];
[aCoder encodeInteger:_age forKey:@"age"];
[aCoder encodeObject:_className forKey:@"className"];
[aCoder encodeObject:_classID forKey:@"classID"];
}