blocks|key|480540|text|您可以使用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|480541|#include+<boost/serialization/vector.hpp>|code-block|syntax|javascript|480542|序列化你的向量。点击这里阅读教程：http://www.boost.org/libs/serialization/doc/tutorial.html#stl+`|offset|length|480543|entityMap|0|LINK|mutability|MUTABLE|url|http://www.boost.org/libs/serialization/doc/tutorial.html#stl^0|0|0|H|1P|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

You can use

<pre><code>#include &lt;boost/serialization/vector.hpp&gt;
</code></pre>

to serialize your vector. Read a tutorial here: <a href="http://www.boost.org/libs/serialization/doc/tutorial.html#stl" rel="nofollow">http://www.boost.org/libs/serialization/doc/tutorial.html#stl</a>
`

blocks|key|263681|text|使用boost::serialization。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|263682|如果你不想使用boost+-写大小和vector。|263683|size_t+sz+=+myVector.size();
FILE.write(reinterpret_cast<const+char*>(&sz),+sizeof(sz));
FILE.write(reinterpret_cast<const+char*>(&myVector[0]),+sz+*+sizeof(myVector[0]));|code-block|syntax|javascript|263684|entityMap^0|2|K|0|7|5|I|6|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@$9|S|A|T|B|C]|$9|U|A|V|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|W|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|X|8|@]|D|@]|E|$]]]|N|$]]

Use <code>boost::serialization</code>.

If you don't want use <code>boost</code> - write size and <code>vector</code>.

<pre><code>size_t sz = myVector.size();
FILE.write(reinterpret_cast&lt;const char*&gt;(&amp;sz), sizeof(sz));
FILE.write(reinterpret_cast&lt;const char*&gt;(&amp;myVector[0]), sz * sizeof(myVector[0]));
</code></pre>

blocks|key|263730|text|在阅读vector之前，你应该调整它的大小：yourVector.size(numberOfElementsYouRead)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|263731|此外，sizeof(vector<your_type>)只是vector对象内部实现的大小；向量元素的大小是sizeof(std::vector<your_type>::value_type)。|263732|然后像这样读下去：|263733|file.read(reinterpret_cast<char+*>(&myVector[0]),+sizeof(vector<int>::element_type)+*+element_count);+|code-block|syntax|javascript|263734|entityMap^0|3|6|M|14|0|3|P|U|6|1I|16|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]|$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|V|8|@$9|W|A|X|B|C]|$9|Y|A|Z|B|C]|$9|10|A|11|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|12|8|@]|D|@]|E|$]]|$1|J|3|K|5|L|7|13|8|@]|D|@]|E|$M|N]]|$1|O|3|-4|5|6|7|14|8|@]|D|@]|E|$]]]|P|$]]

Before reading <code>vector</code>, you should resize it: <code>yourVector.size(numberOfElementsYouRead)</code>.

Besides, <code>sizeof(vector&lt;your_type&gt;)</code> is just the size of the <code>vector</code> object internal implementation; vector element size is <code>sizeof(std::vector&lt;your_type&gt;::value_type)</code>.

Then read it like this:

<pre><code>file.read(reinterpret_cast&lt;char *&gt;(&amp;myVector[0]), sizeof(vector&lt;int&gt;::element_type) * element_count); 
</code></pre>

blocks|key|263760|text|尝试使用ostream_iterator/ostreambuf_iterator、istream_iterator/istreambuf_iterator和STL+copy方法：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|263761|#include+<algorithm>
#include+<iostream>
#include+<iterator>
#include+<vector>

#include+<fstream>+//+looks+like+we+need+this+too+(edit+by+π)

std::string+path("/some/path/here");

const+int+DIM+=+6;
int+array[DIM]+=+{1,2,3,4,5,6};
std::vector<int>+myVector(array,+array+%2B+DIM);
std::vector<int>+newVector;

std::ofstream+FILE(path,+std::ios::out+%7C+std::ofstream::binary);
std::copy(myVector.begin(),+myVector.end(),+std::ostreambuf_iterator<char>(FILE));

std::ifstream+INFILE(path,+std::ios::in+%7C+std::ifstream::binary);
std::istreambuf_iterator+iter(INFILE);
std::copy(iter.begin(),+iter.end(),+std::back_inserter(newVector));|code-block|syntax|javascript|263762|entityMap^0|4|G|L|J|15|G|1M|J|2A|4|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]|$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]]|$1|K|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]]|L|$]]

Try using an <code>ostream_iterator</code>/<code>ostreambuf_iterator</code>, <code>istream_iterator</code>/<code>istreambuf_iterator</code>, and the STL <code>copy</code> methods:

<pre><code>#include &lt;algorithm&gt;
#include &lt;iostream&gt;
#include &lt;iterator&gt;
#include &lt;vector&gt;

#include &lt;fstream&gt; // looks like we need this too (edit by π)

std::string path("/some/path/here");

const int DIM = 6;
int array[DIM] = {1,2,3,4,5,6};
std::vector&lt;int&gt; myVector(array, array + DIM);
std::vector&lt;int&gt; newVector;

std::ofstream FILE(path, std::ios::out | std::ofstream::binary);
std::copy(myVector.begin(), myVector.end(), std::ostreambuf_iterator&lt;char&gt;(FILE));

std::ifstream INFILE(path, std::ios::in | std::ifstream::binary);
std::istreambuf_iterator iter(INFILE);
std::copy(iter.begin(), iter.end(), std::back_inserter(newVector));
</code></pre>

blocks|key|480729|text|我使用的事实是，data()方法返回一个可用于读取和写入的地址。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|480730|//假设outf是一个可写的文件指针(二进制)。//将myVector.size()写入文件，然后|480731|fwrite(myVector.data(),+sizeof(decltype(myVector)::value_type),+myVector.size(),+outf);|code-block|syntax|javascript|480732|阅读：|480733|//从文件中读取MyVector.size()+as+nv，inpf为读取文件指针|480734|MyVector.resize(nv);
fread(MyVector.data(),+sizeof(decltype(MyVector)::value_type),+nv,+inpf);|480735|坚持使用文件io中的旧方法，但请忽略它(即使它可能会激怒您：)。|480736|一个缺点是这种方式不支持字节序。|480737|entityMap^0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|Y|8|@]|9|@]|A|$]]|$1|M|3|N|5|F|7|Z|8|@]|9|@]|A|$G|H]]|$1|O|3|P|5|6|7|10|8|@]|9|@]|A|$]]|$1|Q|3|R|5|6|7|11|8|@]|9|@]|A|$]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

I used the fact that the data() method returns an address you can use for reading AND for writing. 

// Assume outf is a writable filepointer (binary).
// write myVector.size() to file, then

<pre><code>fwrite(myVector.data(), sizeof(decltype(myVector)::value_type), myVector.size(), outf);
</code></pre>

to read:

// read MyVector.size() from file as nv, inpf is read filepointer

<pre><code>MyVector.resize(nv);
fread(MyVector.data(), sizeof(decltype(MyVector)::value_type), nv, inpf);
</code></pre>

clinging to old ways in file io, but please ignore that (even if it might irritate you :)).

A weakness is that endianness is unsupported in this way.

That is the point. How to write and read binary files with std::vector inside them?

I was thinking something like:

<pre><code>//============ WRITING A VECTOR INTO A FILE ================
const int DIM = 6;
int array[DIM] = {1,2,3,4,5,6};
std::vector&lt;int&gt; myVector(array, array + DIM);
ofstream FILE(Path, ios::out | ofstream::binary);
FILE.write(reinterpret_cast&lt;const char *&gt;(&amp;myVector), sizeof(vector) * 6);
//===========================================================
</code></pre>

But I don't know how to read this vector. Because I thought that the following was correctly but it isn't:

<pre><code>ifstream FILE(Path, ios::in | ifstream::binary);
FILE.read(reinterpret_cast&lt;const char *&gt;(&amp;myVector), sizeof(vector) * 6);
</code></pre>

So, how to perform the operation?

Reading and writing a std::vector into a file correctly

这就是问题所在。如何写入和读取内部带有std::vector的二进制文件？我是这样想的：//============ WRITING A VECTOR INTO A FILE ================const int DIM = 6;int array[DIM] = {1,2,3,4,5,6};std::ve...

问正确地将std::vector读写到文件中
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