在类中初始化 NSString* 指针的方式
我在我的类中使用 NSString ，并且经常需要将字符串值复制到另一个类。但我的问题是我应该如何初始化字符串，例如 init？ （值是类成员，以下调用在 init 中）
value = [NSString stringWithCString:inStrning encoding:NSASCIIStringEncoding];
或者
value = [[NSString alloc] initWithCString:inStrning encoding:NSASCIIStringEncoding];
这里有什么区别？ init 完成后，第一次调用中分配的内存是否会释放？ 我使用 value 作为 assign 属性。使用copy会更好吗？
当我使用某种方法将字符串传递给类时复制字符串怎么样？示例：
-(id) initWithObjectTypeStr:(NSString*)inTypeStr
{
...
objectTypeStr = [NSString stringWithString:inType];
//or
objectTypeStr = [[NSString alloc] initWithString:inType];
}
objectTypeStr 未定义为属性，因此它具有默认属性（我认为assign）。
在这种情况下使用的最佳做法是什么？
I'm using NSString in my classes and often need to copy string value to another class. But my question is how should I initialize string in, for example init?
(value is class member and the following calls are in init)
value = [NSString stringWithCString:inStrning encoding:NSASCIIStringEncoding];
or
value = [[NSString alloc] initWithCString:inStrning encoding:NSASCIIStringEncoding];
What is the difference here? Does a memory allocated in 1st call released when init finishes?
I'm using value as a assign property. Would it be better to use copy?
And what about copying string when I'm passing it to class using some method? Example:
-(id) initWithObjectTypeStr:(NSString*)inTypeStr
{
...
objectTypeStr = [NSString stringWithString:inType];
//or
objectTypeStr = [[NSString alloc] initWithString:inType];
}
objectTypeStr is not defined as property so it has default properties (assign I think).
What is the best practice to use in this case?
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归还您拥有的字符串，您必须释放它。
返回一个自动释放对象，该对象将由自动释放池释放并清理。
我建议您阅读 内存管理文档。
Gives back a string you own, you will have to release it.
Returns an autorelease object that will release and cleaned up by the autoreleasepool.
I would suggest you read the memory management documentation.
不同之处在于，在本例中
objectTypeStr = [NSString stringWithString:inType];objectTypeStr是自动释放的，并且您不拥有该对象。而在
objectTypeStr = [[NSString alloc] initWithString:inType];您拥有该对象的所有权，因为您使用 alloc 或 new 分配它，因此您有责任在使用后释放它
The difference is that in this case
objectTypeStr = [NSString stringWithString:inType];objectTypeStris auto-released and you dont own the object.Whereas in
objectTypeStr = [[NSString alloc] initWithString:inType];you take ownership of the object since you are allocating it using alloc or new so its your responsibility to release it after its use