ios iOS中的[Class new]和[[Class alloc] init]有什么区别？
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What is the difference between [Class new] and [[Class alloc] init] in iOS?
提问by Prasad G
Possible Duplicate:
alloc, init, and new in Objective-C
I am a little confused about [Class new]and [[Class alloc] init]. I have defined an object contentusing [Class new]and [[Class alloc] init].
我对[Class new]和 有点困惑[[Class alloc] init]。我已经content使用[Class new]and 定义了一个对象[[Class alloc] init]。
(1). NSMutableArray *content = [NSMutableArray new];
(2). NSMutableArray *content = [[NSMutableArray alloc] init];
My question is about the differences between [Class new]and [[Class alloc] init]. For me, (1) and (2) are similar. If (1) and (2) are similar, then why do we use [[Class alloc] init]most of the time, compared to [Class new]? I think that there must be some difference.
我的问题是关于之间的差异[Class new]和[[Class alloc] init]。对我来说，（1）和（2）是相似的。如果 (1) 和 (2) 相似，那么与 相比，为什么我们[[Class alloc] init]大部分时间都使用[Class new]？我认为一定有一些区别。
Kindly explain the differences, pros & cons of both?
请解释两者的区别，优缺点？
回答by Shantanu
Alloc:Class method of NSObject. Returns a new instance of the receiving class.
Alloc：NSObject 的类方法。返回接收类的新实例。
Init: Instance method of NSObject. Implemented by subclasses to initialize a new object (the receiver) immediately after memory for it has been allocated.
Init: NSObject 的实例方法。由子类实现以在为其分配内存后立即初始化新对象（接收器）。
New: Class method of NSObject. Allocates a new instance of the receiving class, sends it an init message, and returns the initialized object.
新：NSObject 的类方法。分配接收类的新实例，向它发送一个 init 消息，并返回初始化的对象。
Release: Instance method of NSObject delegate. Decrements the receiver's reference count.
Release: NSObject 委托的实例方法。减少接收者的引用计数。
Autorelease: Instance method of NSObject delegate. Adds the receiver to the current autorelease pool.
Autorelease: NSObject 委托的实例方法。将接收器添加到当前的自动释放池。
Retain:Instance method of NSObject delegate. Increments the receiver's reference count.
Retain：NSObject 委托的实例方法。增加接收者的引用计数。
Copy:Instance method of NSObject delegate. Returns a new instance that's a copy of the receiver.
复制：NSObject 委托的实例方法。返回一个新实例，它是接收器的副本。
So to conclude we can say that
所以总而言之，我们可以说
alloc goes with init
alloc 与 init 一起使用
new = alloc + init
新 = 分配 + 初始化
回答by dreamlax
The +newmethod is simply shorthand for +allocand -init. The ownership semantics are identical. The only benefit to using +newis that it is more concise. If you need to provide arguments to the class's initialiser, you will have to use the +allocand -initWith...methods instead.
该+new方法只是+allocand 的简写-init。所有权语义是相同的。使用的唯一好处+new是它更简洁。如果需要为类的初始化程序提供参数，则必须改用+alloc和-initWith...方法。
回答by Cehh?ro
Here: alloc, init, and new in Objective-C
此处：Objective-C 中的 alloc、init 和 new
Basically it's a question of modern versus traditional. The most direct advantage of init over new is that there are many custom init methods.
基本上这是一个现代与传统的问题。init 相对于 new 最直接的优点是有很多自定义的 init 方法。
