保存自定义对象数组、字典到文件
2016-03-22 本文已影响165人
不舍
在ios中,要保存普通的数组到文件可以直接调用-wirteToFile:atomically:方法写入,并且可以通过NSArray的方法-initWithContentOfFile:来读文件初始化数组。然而,当要保存的数组中存储的数据对象是自定义对象时,就得通过对象归档的方法来实现了,具体来说
一、自定义对象实现归档协议,并实现方法- (id)initWithCoder:和方法- (void)encodeWithCoder:
@interface CourseModel : CYZBaseModel <NSCoding>
- (id)initWithCoder:(NSCoder *)aDecoder{ self = [super init]; if (self) { self.courseName = [aDecoder decodeObjectForKey:@"courseName"]; self.courseTeacher = [aDecoder decodeObjectForKey:@"courseTeacher"]; self.courseTime = [aDecoder decodeObjectForKey:@"courseTime"]; self.courseLocation = [aDecoder decodeObjectForKey:@"courseLocation"]; self.shouldUseTip = [aDecoder decodeBoolForKey:@"shouldUseTip"]; self.row = [aDecoder decodeIntegerForKey:@"row"]; self.section = [aDecoder decodeIntegerForKey:@"section"]; } return self;}- (void)encodeWithCoder:(NSCoder *)aCoder{ [aCoder encodeObject:self.courseName forKey:@"courseName"]; [aCoder encodeObject:self.courseTeacher forKey:@"courseTeacher"]; [aCoder encodeObject:self.courseTime forKey:@"courseTime"]; [aCoder encodeObject:self.courseLocation forKey:@"courseLocation"]; [aCoder encodeBool:self.shouldUseTip forKey:@"shouldUseTip"]; [aCoder encodeInteger:self.row forKey:@"row"]; [aCoder encodeInteger:self.section forKey:@"section"];}
二、获得保存文件的路径
- (NSString *)filePath{
return [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES)objectAtIndex:0]stringByAppendingPathComponent:@"course.plist"];
}
三、调用NSKeyedArchived类的类方法:- (void)archiveRootObject:toFile:写入文件
NSString *path = [self filePath];
[NSKeyedArchiver archiveRootObject:self.allCourses toFile:path];
四、调用NSKeyedUnarchiver类的类方法:- (id)unarchiveObjectWithFile:读文件
NSString *path = [self filePath];
self.allCourses = [NSKeyedUnarchiver unarchiveObjectWithFile:path]; if (self.allCourses == nil) {
self.allCourses = [NSMutableArray array];
}