斯威夫特数组传值...相同的内存地址？ [英] Swift Array Pass by Value...same memory address?

问题描述

有人可以请清除此为我说话。

我的理解（思维）斯威夫特传递数组按值，因为它是一个结构。

但是，当我通过赛格瑞数组传递到下一个视图控制器在我看来，它是通过引用传递，因为当我检查数组它们是相同的内存地址。

这是我如何检查

 的println（\\（unsafeAddressOf（运行）））// 0x0000000174240c00
 

我还以为这些内存地址会有所不同？还是我只是混淆自己。

运行/ StaffTask类无论是从NSObject的继承降耗的目的。

 类运行：NSObject的，NSCoding {}
 

此外，如果我在数组中访问一个项目

  VAR的服务= self.staffTasks [indexPath.row]
 

和编辑该值，无论该服务变量的值和阵列中的元素被更新。他们有相同的内存地址，如图

 的println（\\（unsafeAddressOf（服务））\\（unsafeAddressOf（self.staffTasks [indexPath.row]）））
 

另外...

staffTasks是一个较大的阵列称为运行的一个子集

当我搜索服务对象，具有较大的盘，我发现他们也是相同的内存地址

 如果让指数=查找（self.runs，self.staff）{
    的println（本地\\（unsafeAddressOf（self.staff））主目录\\（unsafeAddressOf（self.runs [指数]）））
}
 

我使用NSCoding救我的对象，所以我想我需要找到服务对象大集内，更换对象，然后保存出来。

但原来我不需要，我能够编辑服务变量，运行的阵列自动更新......像一个引用类型会。

传递？ ..设定瓦尔

在prepare为SEGUE，只是用标准的方式设置在第二VC的局部变量，VAR runsInSecondVC =运行。不使用，和放大器;指针或任何其他古怪

感谢您的帮助。

类基本详情

 类运行：NSObject的，NSCoding {    VAR runDate：NSDate的！
    VAR staffName：串！
    VAR staffEmail：串！
    VAR runTasks：[StaffTask]！}类StaffTask：NSObject的，NSCoding {    VAR TASKNAME：字符串
    VAR taskTime：NSInteger的
    VAR CLIENTNAME：串！
}
 

这是这些类的基础。没有什么复杂的。

解决方案

  

按值传递数组

没有。斯威夫特阵列是一个的值类型的。这并不意味着他们是通过按值。这意味着你可以通过变异的引用方式数组，而不会影响其他引用到该数组已被分配。

Can someone please clear this up for me.

I understand (thought) Swift passes arrays by value as it is a struct.

But when I pass an array via segue to the next view controller it appears to me that it is passing by reference, as when I check the memory address of the array they are the same.

This is how I'm checking

println("\(unsafeAddressOf(runs))") // 0x0000000174240c00

I would have thought these memory addresses would be different ? Or am I just confusing myself.

The Run / StaffTask classes both inherit from NSObject for saving purposes.

class Run: NSObject, NSCoding { } 

Furthermore, if I access a item in the array

var service = self.staffTasks[indexPath.row]

and edit the value, both the service variable value and the element in the array are updated. They have the same memory address, as shown by

println("\(unsafeAddressOf(service))  \(unsafeAddressOf(self.staffTasks[indexPath.row]))")

Also...

staffTasks are a subset of a larger array called runs

When I search for the service object, with the larger set, I find that they are also the same memory address

if let index = find(self.runs, self.staff) {
    println("local \(unsafeAddressOf(self.staff))  main list \(unsafeAddressOf(self.runs[index]))")
}

I am using NSCoding to save my objects, so I thought I would need to find the service object within the larger set, replace that object and then save them out.

But turns out I don't need to, I am able to edit the service variable and array of runs is updated on automatically ... like a reference type would be.

Passing? .. setting the Var

in prepare for segue, just setting the local var in the second VC using the standard way, var runsInSecondVC = runs. Not using, &pointers or any other weirdness.

Thanks for any help.

Class Basic Details

class Run: NSObject, NSCoding {

    var runDate:NSDate!
    var staffName:String!
    var staffEmail:String!
    var runTasks:[StaffTask]!

}

class StaffTask: NSObject, NSCoding {

    var taskName:String
    var taskTime:NSInteger
    var clientName:String!
}

These are the basic of these classes. Nothing complicated.

解决方案

passes arrays by value

No. Swift arrays are a value type. This does not mean they are pass-by-value. It means that you can mutate an array by way of a reference without affecting other references to which that array has been assigned.

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