寫一個setter方法用于完成@property?(nonatomic,retain)NSString?*name,寫一個setter方法用于完成@property(nonatomic，copy)NSString?*name
答：
-?(void)setName:(NSString*)str?{
if?(_name?!=?str)?{
[_name?release];
_name?=?[str?retain];
}
}
-?(void)setName:(NSString?*)str?{
if?(_name?!=?str)?{
[_name?release];
_name?=?[str?copy];
}
}
-?(void)setName:(NSString*)str?{
if?(_name?!=?str)?{
[_name?release];
_name?=?[str?retain];
}
}
-?(void)setName:(NSString?*)str?{
if?(_name?!=?str)?{
[_name?release];
_name?=?[str?copy];
}
}
