字符串用copy
數(shù)組用strong
@property (nonatomic,retain) NSString * name;
- (void)setName:(NSString*)name
{
[name retain]; // 把傳進(jìn)來的對(duì)象引用計(jì)數(shù)加一
[_name release]; // 把_name以前的對(duì)象release一次
_name = name; // 把name的對(duì)象地址給_name 這時(shí)name 和_name共同對(duì)象的引用為2
}
@property (nonatomic ,assign) NSString *name
- (void)setName:(NSString*)name
{
_name = name; // name和_name 引用計(jì)數(shù)為1;
}
@property (nonatomic , copy) NSString * name
- (void)setName: (NSString*)name
{
[_name release]; //把_name以前的對(duì)象release一次
_name = [name copy]; // 把name 的對(duì)象拷貝一份給_name 這時(shí)_name 的引用計(jì)數(shù)為1 而name的引用計(jì)數(shù)不變
}
