iOS数据持久化注意点

来源：互联网发布：数据化发展编辑：程序博客网时间：2024/05/18 17:02

一、nsuserdefault：
1：nsuserDefault 不能存储自定义对象，其支持的数据格式有：NSNumber（Integer、Float、Double等）、NSString、NSDate、NSArray（成员必须也是支持的格式类型）、NSDictionary（同NSArray）。

二、归档：
1.归档保存的自定对象的重写归档方法时，需要将基本数据类型转成nsnumber对象。

2.归档需要重写两个方法：

//序列化- (void)encodeWithCoder:(NSCoder *)coder{    [coder encodeObject:@(self.cellType) forKey:CELLTYPE];    [coder encodeObject:self.cellContent forKey:CELLCONTENT];    [coder encodeObject:@(self.cellHeight) forKey:CELLHEIGHT];    [coder encodeObject:self.cellImage forKey:CELLIMAGE];    [coder encodeObject:@(self.isHiddenPlayButton) forKey:ISHIDDENPLAYBUTTON];    [coder encodeObject:self.cellImageUrl forKey:CELLIMAGEURL];    [coder encodeObject:self.cellImageData forKey:CELLIMAGEDATA];    [coder encodeObject:self.cellVideoUrl forKey:CELLVIDEOURL];}//反序列化- (instancetype)initWithCoder:(NSCoder *)coder{    self = [super init];    if (self) {        self.cellType = (CellType)[[coder decodeObjectForKey:CELLTYPE] integerValue];        self.cellContent = [coder decodeObjectForKey:CELLCONTENT];        self.cellHeight = [[coder decodeObjectForKey:CELLHEIGHT] floatValue];        self.cellImage = [coder decodeObjectForKey:CELLIMAGE];        self.isHiddenPlayButton = [[coder decodeObjectForKey:ISHIDDENPLAYBUTTON] boolValue];        self.cellImageUrl = [coder decodeObjectForKey:CELLIMAGEURL];        self.cellImageData = [coder decodeObjectForKey:CELLIMAGEDATA];        self.cellVideoUrl = [coder decodeObjectForKey:CELLVIDEOURL];    }    return self;}

3.归档只能每次保存一个自定义对象。

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