blocks|key|1210992|text|向量在结构中工作得很好：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1210993|#include+<vector>

struct+Test+{
++++std::vector<int>+Numbers;
};|code-block|syntax|javascript|1210994|我不知道你到底想做什么，但我认为这是近在咫尺。|1210995|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

vector works just fine in structs:

<pre><code>#include &lt;vector&gt;

struct Test {
 std::vector&lt;int&gt; Numbers;
};
</code></pre>

I'm not sure what you're really trying to do but I think this comes close.

blocks|key|1241873|text|您可以使用指向int的指针--即，|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1241874|struct+Test{++
++++int+*Number;++
};|code-block|syntax|javascript|1241875|然后，您可以在将来的任何时候将它分配给您喜欢大小的数组：|1241876|t.Number+=+new+int[5];|1241877|但是正如其他人已经说过的那样，带有小"v“的std::vector工作得很好；一定要使用#include+<vector>，以便编译器知道您在说什么。|1241878|entityMap^0|7|3|0|0|0|0|M|B|18|H|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|W|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|Y|8|@$9|Z|A|10|B|C]|$9|11|A|12|B|C]]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|13|8|@]|D|@]|E|$]]]|R|$]]

You can use a pointer to <code>int</code> -- i.e.,

<pre><code>struct Test{ 
 int *Number; 
};
</code></pre>

Then you can assign this at any future time to point to an array of your preferred size:

<pre><code>t.Number = new int[5];
</code></pre>

But as other posters have already said, <code>std::vector</code>, with a small "v", works fine; be sure to <code>#include &lt;vector&gt;</code> so the compiler knows what you're talking about.

blocks|key|1211027|text|一招就是这么做|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1211028|struct+Test+{
++int+Numbers[1];
};|code-block|syntax|javascript|1211029|初始化结构时，需要使用自己的分配函数。|1211030|struct+Test+*NewTest(int+sizeOfNumbers)+{
++return+(struct+Test*)malloc(sizeof(struct+Test)+%2B+sizeof(int)*(sizeOfNumbers+-+1));
}|1211031|然后，您就可以通过使用|1211032|struct+Test+*test1+=+NewTest(10);
test1->Numbers[0]...
test1->Numbers[1]...
test1->Numbers[9]...|1211033|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

One trick to do this

<pre><code>struct Test {
 int Numbers[1];
};
</code></pre>

when you initialize the struct, you need to use your own allocation function.

<pre><code>struct Test *NewTest(int sizeOfNumbers) {
 return (struct Test*)malloc(sizeof(struct Test) + sizeof(int)*(sizeOfNumbers - 1));
}
</code></pre>

then, you will be able to access the numbers by using,

<pre><code>struct Test *test1 = NewTest(10);
test1-&gt;Numbers[0]...
test1-&gt;Numbers[1]...
test1-&gt;Numbers[9]...
</code></pre>

blocks|key|1211040|text|new+int[3]的返回值是int*，而不是int。要使您的代码工作，您可以：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1211041|struct+Test+{++
++++int*+Number;++
};

int+main()+{
++++Test+t1;++
++++t1.Number+=+new+int[4];+//+Note+this+should+be+4+so+that+index+3+isn't+out+of+bounds
++++t1.Number[3]+=+6;
++++delete+t1.Number;

++++return+0;
}|code-block|syntax|javascript|1211042|但是，您应该真正使用std::vector，而不是静态数组。向量在结构中工作得很好：|1211043|#include+<vector>

struct+Test+{++
++++std::vector<int>+Number;++
};

int+main()+{
++++Test+t1;++
++++t1.Number.resize(4);+++
++++t1.Number[3]+=+6;

++++return+0;
}|1211044|entityMap^0|0|A|F|4|N|3|0|0|A|B|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]|$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|M|3|N|5|H|7|11|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|12|8|@]|D|@]|E|$]]]|P|$]]

The return value of <code>new int[3]</code> is an <code>int*</code> not an <code>int</code>. To make your code work you can do:

<pre><code>struct Test { 
 int* Number; 
};

int main() {
 Test t1; 
 t1.Number = new int[4]; // Note this should be 4 so that index 3 isn't out of bounds
 t1.Number[3] = 6;
 delete t1.Number;

 return 0;
}
</code></pre>

However you should really use a <code>std::vector</code> rather than a static array. Vectors work just fine inside structs:

<pre><code>#include &lt;vector&gt;

struct Test { 
 std::vector&lt;int&gt; Number; 
};

int main() {
 Test t1; 
 t1.Number.resize(4); 
 t1.Number[3] = 6;

 return 0;
}
</code></pre>

I was wondering if there was a way to initialize an array out of a variable from a struct. Say you have a struct like this- 

<pre><code>struct Test{ 
 int Number; 
};
</code></pre>

And you wanted to initialize the int Number to become an array. 
I've already tried this, and it doesn't work: 

<pre><code>Test t1; 
t1.Number = new int[3]; 
t1.Number[3] = 6;
</code></pre>

I know ISO C++ forbids resizing arrays, but if there was a way to initialize the integer to be an array, that's not really resizing(isn't it?)
Also, vectors don't work inside of structs. I get a "Vector does not name a type" error. 

P.S., I can't do this either: 

<pre><code>struct Test{ 
 int Number[5]; 
};
</code></pre>

Because at that time I don't know the size of the array I want.

Array Initialization from a struct

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我想知道是否有办法从一个结构变量中初始化一个数组。如果你有这样的结构-struct Test{      int Number;  };您希望初始化int 数字，使其成为一个数组。我已经试过了，但没有用：Test t1;  t1.Number = new int[3];   t1.Number[3] = 6;我知道C+...

问从结构中初始化数组
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