外管局指针的指针（以及引用参考）在C＃ [英] SAFE Pointer to a pointer (well reference to a reference) in C#

问题描述

在C＃应用程序我的工作我有一个很长的标识如下： -

In a C# application I am working on I have a very long identifier as follows:-

foo.bar.bwah.blah.whatever.very.very.huge

每当我引用这个对象这是一个绝对的噩梦，不幸的是我确实需要引用了很多： -

Whenever I to reference this object it's an absolute nightmare, and unfortunately I do need to reference it a lot:-

var something = foo.bar.bwah.blah.whatever.very.very.huge.a;
var somethingElse = foo.bar.bwah.blah.whatever.very.very.huge.b;
foo.bar.bwah.blah.whatever.very.very.huge.c = 12;

等。等等。

我想用某种形式的小得多别名更新此code，问题然而，我想改变底层参考，并具有别名更新还的没有明确更新别名。

I want to update this code using a far smaller alias of some kind, the problem is however that I want to change the underlying reference, and have the alias update also without explicitly updating the alias.

目前，如果我做到以下几点： -

Currently if I do the following:-

foo.bar.bwah.blah.whatever.very.very.huge.a = "hello";
string shorter = foo.bar.bwah.blah.whatever.very.very.huge.a;
foo.bar.bwah.blah.whatever.very.very.huge.a = "world";
Console.WriteLine(shorter);

这将输出你好。我想实现的是类似以下内容： -

It will output "hello". What I want to achieve is something like the following:-

foo.bar.bwah.blah.whatever.very.very.huge.a = "hello";
string** shorterPointer = &foo.bar.bwah.blah.whatever.very.very.huge.a;
foo.bar.bwah.blah.whatever.very.very.huge.a = "world";
Console.WriteLine(**shorter);

这将输出世界的要求。

Which would output "world" as required.

我相信你可以做到这样的事情使用不安全的code在C＃中，但我的不能的做到这一点，我要使用安全的code而已。

I believe you can achieve something like this using unsafe code in C#, however I cannot do that, I have to use safe code only.

没有任何人有任何想法我会如何实现这一目标？

Does anybody have any ideas how I might achieve this?

请注意：这个问题是不是字符串是不可变的，我知道他们是 - 事实上，我认为他们是对这个问题的目的。这也许可以更简单，如果我用一些其他类型的......所以当我将你好到随后的世界到，我的实例化不同的对象的每一次，所以我存储的参考经过重新分配到一个无效。

Please Note: This question is not about strings being immutable, I know they are - in fact I assumed they are for the purposes of the question. It might perhaps be simpler if I used some other type... so when I assign "hello" to a then "world" to a, I am instantiating different objects on each occasion, hence my stored reference to a becomes invalid after re-assignment.

推荐答案

出的一种方式是使用一个或一对lambda表达式

One way out is to use one or a pair of lambdas.

例如：

Func<string> getter = () => blah_de_blah;
Action<string> setter = x => blah_de_blah = x;

现在，您可以使用getter和setter来读取和写入的长标识符。​​

Now, you can use getter and setter to read and write the long identifier.

然而，由于你的点是成员访问中，绕了最简单的方法是采取引用直接父，像这样：

However, since your dots are member accessors, the easiest way of going about it is to take a reference to the immediate parent, like so:

var myHuge = foo.bar.bwah.blah.whatever.very.very.huge;
// now access myHuge.a everywhere

这是在任何情况下很好的做法，作为一项长期的虚线EX pression这样是违反的德米特，该抑制的codeBase的灵活性法 - 它需要太多的地方太多信息

This is good practice in any case, as a long dotted expression like this is a violation of the Law of Demeter, which inhibits the flexibility of the codebase - it requires too much information in too many places.

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