blocks|key|895745|text|因为C%2B%2B03没有向量文字。使用数组有时可以生成更简洁的代码。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|895746|与数组初始化相比：|895747|char+arr[4]+=+{'A',+'B',+'C',+'D'};|code-block|syntax|javascript|895748|向量初始化可能看起来有点冗长|895749|std::vector<char>+v;
v.push_back('A');
v.push_back('B');
...|895750|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Because C++03 has no vector literals. Using arrays can sometime produce more succinct code.

Compared to array initialization:

<pre><code>char arr[4] = {'A', 'B', 'C', 'D'};
</code></pre>

vector initialization can look somewhat verbose

<pre><code>std::vector&lt;char&gt; v;
v.push_back('A');
v.push_back('B');
...
</code></pre>

blocks|key|1110584|text|我选择C%2B%2B0x中提供的std::array，而不是普通数组，后者也可以像标准数组一样使用初始化器列表进行初始化|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1110585|https://en.cppreference.com/w/cpp/container/array|offset|length|1110586|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|1D|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@$D|O|E|P|1|Q]]|A|$]]|$1|F|3|-4|5|6|7|R|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|C]]]]

I'd go for std::array available in C++0x instead of plain arrays which can also be initialized like standard arrays with an initializer list

<a href="https://en.cppreference.com/w/cpp/container/array" rel="nofollow noreferrer">https://en.cppreference.com/w/cpp/container/array</a>

blocks|key|895854|text|我认为这是因为许多C%2B%2B程序员来自C语言，他们还不了解使用vector的好处以及它的容器中免费提供的所有额外的STL好处。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|895855|entityMap^0|T|6|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

I think this is because a lot of C++ programmers come from C and don't yet understand the advantages of using <code>vector</code> and all the extra STL goodies that come for free with its containers.

blocks|key|895908|text|您对数组有更多的控制|type|unstyled|depth|inlineStyleRanges|entityRanges|data|895909|这样如何：|895910|1)您正在处理的是巨大的数据集，其中的数据必须是映射文件，并且由于其大小，不能使用malloc或new进行分配。在这种情况下，如果你一开始没有预留足够的地址空间，担心该怎么做可能是没有意义的，尽管我认为你可以取消映射-扩展-重新映射文件，除非被地址碎片或我的第二点禁止。|offset|length|style|CODE|895911|2)使用无锁多处理的代码。停止线程重新分配(或任何其他"STL好东西“)的性能影响可能是不可接受的，因此使用数组，你有更多的控制，在你调整任何大小之前，你可能需要调用很多函数来暂停其他线程。|895912|顺便说一句，我通常同时处理1和2。使用C%2B%2B编译时，结构%2B指针的数组工作得很好，因为您仍然可以在代码中的其他地方使用一些C%2B%2B特性。我敢肯定，如果我足够努力，我能想到更多的例子|895913|entityMap^0|0|0|15|6|1C|3|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|R|8|@$F|S|G|T|H|I]|$F|U|G|V|H|I]]|9|@]|A|$]]|$1|J|3|K|5|6|7|W|8|@]|9|@]|A|$]]|$1|L|3|M|5|6|7|X|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|O|$]]

You have much more control with arrays

How about:

1) you are dealing with colossal data sets where the data has to be mapped files and not allocated with <code>malloc</code> or <code>new</code> because of its size. Under this scenario worrying about what to do if you didn't reserve enough address space at the beginning may be moot, though I suppose you could unmap - extend - remap the file, unless prohibited by address fragmentation or my second point.

2) Code that uses lockless multiprocessing. Performance hits of stopping the threads for re-allocation (or any other "STL goodie") may be unacceptable, hence use arrays, you have got much more control, you may need to call a lot of functions to pause other threads before you resize anything. 

BTW, I'm usually dealing with 1 and 2 at the same time. Arrays of structures + pointers work wonderfully, Compiling with C++ because you you can still use some C++ features elsewhere in the code. I'm sure I could think of many more examples if I tried hard enough

I'm currently seeing a lot of questions which are tagged C++ and are about handling arrays. 
There even are questions which ask about methods/features for arrays which a <code>std::vector</code> would provide without any magic.

So I'm wondering why so much developers are chosing arrays over <code>std::vector</code> in C++?

Advantages of using arrays instead of std::vector?

容器

我最近看到了很多标记为C++的问题，它们都是关于处理数组的。甚至还有关于数组的方法/特性的问题，std::vector不需要任何魔法就能提供这些方法/特性。所以我想知道为什么这么多开发人员在C++中选择数组而不是std::vector？

问使用数组而不是std::vector的优点？
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