写一个setter方法用于完成@property(nonatomic, strong)NSString *name,
写一个setter方法用于完成@property(nonatomic, copy)NSString *name
- (void)setName:(NSString*)str //retain
{
[str retain];
[_name release];
_name = str;
}
- (void)setName:(NSString *)str //copy
{
id t = [str copy];
[_name release];
_name = t;
}