blocks|key|3342489|text|我不确定你想做的事情是不是可能。<<运算符不是虚拟的。因此，您可以定义yourstream+&operator+<<+(yourstream+&strm,+int+i)来执行您想要的字节顺序转换和计数，并且当您的代码直接调用它时，它将工作。但是，如果您将一个yourstream对象传递给一个需要ostream的函数，那么每当该函数调用<<时，它都会转到原始的ostream版本，而不是您的版本。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3342490|据我所知，streams工具已经设置好了，这样您就可以“轻松地”定义一个使用不同类型的缓冲区的新的流类型(例如，字符队列)，并且您可以非常容易地添加对通过<<输出您自己的类的支持。我不认为你打算重新定义它们之间的中间层。|3342491|尤其是，<<接口的全部目的是提供格式良好的文本输出，而听起来您实际上想要的是二进制输出。(否则，引用"endian“就没有任何意义了。)即使假设有某种方法可以做到这一点，我也不知道，它最多只能产生笨拙的二进制输出。例如，考虑最终用户在3D空间中输出点的过载。最终用户版的<<可能会执行类似<<+'('+<<+x+<<+",+"+<<+y+<<+",+"+<<+z+<<+')'的操作。这在文本流中看起来很不错，但它在二进制流中有很多浪费且完全无用的字符，理想情况下只使用<<+x+<<+y+<<+z。(对<<的调用应计为多少次？)|3342492|entityMap^0|G|2|Z|1D|4O|2|0|25|2|0|4|2|3R|2|40|18|6J|E|70|2|0^^$0|@$1|2|3|4|5|6|7|L|8|@$9|M|A|N|B|C]|$9|O|A|P|B|C]|$9|Q|A|R|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|V|8|@$9|W|A|X|B|C]|$9|Y|A|Z|B|C]|$9|10|A|11|B|C]|$9|12|A|13|B|C]|$9|14|A|15|B|C]]|D|@]|E|$]]|$1|J|3|-4|5|6|7|16|8|@]|D|@]|E|$]]]|K|$]]

I'm not sure that what you want to do is possible. The <code>&lt;&lt;</code> operators are not virtual. So you could define <code>yourstream &amp;operator &lt;&lt; (yourstream &amp;strm, int i)</code> to do what you want with the endian conversion and counting, and it will work when your code calls it directly. But if you pass a yourstream object into a function that expects an ostream, any time that function calls <code>&lt;&lt;</code>, it will go to the original ostream version instead of yours.

As I understand it, the streams facilities have been set up so that you can "easily" define a new stream type which uses a different sort of buffer (like, say, a deque of chars), and you can very easily add support for outputting your own classes via <code>&lt;&lt;</code>. I don't think you are intended to be able to redefine the middle layer between those.

And particularly, the entire point of the <code>&lt;&lt;</code> interface is to provide nicely formatted text output, while it sounds like you actually want binary output. (Otherwise the reference to "endian" makes no sense.) Even assuming there is some way of doing this I don't know, it will produce awkward binary output at best. For instance, consider the end user overload to output a point in 3D space. The end user version of <code>&lt;&lt;</code> will probably do something like <code>&lt;&lt; '(' &lt;&lt; x &lt;&lt; ", " &lt;&lt; y &lt;&lt; ", " &lt;&lt; z &lt;&lt; ')'</code>. That will look nice in a text stream, but it's a lot of wasted and completely useless characters in a binary stream, which would ideally just use <code>&lt;&lt; x &lt;&lt; y &lt;&lt; z</code>. (And how many calls to <code>&lt;&lt;</code> should those count as?)

blocks|key|349832|text|规范方法包括定义您自己的streambuf。你应该看看：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|349833|349834|Angelika+LAnger's+articles+on+derivation|unordered-list-item|offset|length|349835|James+Kanze's+articles+on+filtering+streambufs|349836|boost.iostream+(了解IOStreams+|349837|的应用程序示例)|349838|entityMap|0|LINK|mutability|MUTABLE|url|http://www.angelikalanger.com/Articles/Topics.html#CPP|1|http://gabisoft.free.fr/articles-en.html|2|http://www.boost.org/doc/libs/1_37_0/libs/iostreams/doc/index.html^0|0|0|0|Q|0|0|0|M|1|0|0|E|2|0|0^^$0|@$1|2|3|4|5|6|7|Z|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|10|8|@]|9|@]|A|$]]|$1|C|3|D|5|E|7|11|8|@]|9|@$F|12|G|13|1|14]]|A|$]]|$1|H|3|I|5|E|7|15|8|@]|9|@$F|16|G|17|1|18]]|A|$]]|$1|J|3|K|5|E|7|19|8|@]|9|@$F|1A|G|1B|1|1C]]|A|$]]|$1|L|3|M|5|6|7|1D|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|1E|8|@]|9|@]|A|$]]]|O|$P|$5|Q|R|S|A|$T|U]]|V|$5|Q|R|S|A|$T|W]]|X|$5|Q|R|S|A|$T|Y]]]]

The canonical approach consists in defining your own streambuf.
You should have a look at:

<ul>
<li><a href="http://www.angelikalanger.com/Articles/Topics.html#CPP" rel="noreferrer">Angelika LAnger's articles</a> on IOStreams derivation</li>
<li><a href="http://gabisoft.free.fr/articles-en.html" rel="noreferrer">James Kanze's articles</a> on filtering streambufs</li>
<li><a href="http://www.boost.org/doc/libs/1_37_0/libs/iostreams/doc/index.html" rel="noreferrer">boost.iostream</a> for examples of application</li>
</ul>

blocks|key|3129560|text|对于A%2BC)我认为你应该看看facet，它们修改了对象被写成字符的方式。你也可以在这里存储你的对象流传输次数的统计信息。有关示例，请查看How+to+format+my+own+objects+when+using+STL+streams?。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|3129561|对于B)，您需要创建自己的streambuf并将您的ostream连接到该缓冲区(构造函数参数)。请参见Luc's+links+%2B+Deriving+new+streambuf+classes。简而言之，你需要实现一个ostream+(最小)：|3129562|(link)|3129563|xsputn+(将字符数组放入buffer)(link)|unordered-list-item|3129564|
|3129565|sync+(link)|3129566|
+)+|3129567|overflow+(放置单个字符或刷新缓冲区)|3129568|3129569|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/1096291/how-to-format-my-own-objects-when-using-stl-streams/|1|https://stackoverflow.com/questions/524641/how-do-i-create-an-ostream-streambuf/528460#528460|2|https://duckduckgo.com/?q=Deriving%2Bnew%2Bstreambuf%2Bclasses&t=ffab&ia=web|3|http://uw714doc.sco.com/en/SDK_clib/_overflow.html|4|http://www.cplusplus.com/reference/iostream/streambuf/xsputn/|5|http://uw714doc.sco.com/en/SDK_clib/_sync.html^0|1W|1G|0|0|1G|B|1|1U|U|2|0|1|4|3|0|N|4|4|0|0|6|4|5|0|0|0|0^^$0|@$1|2|3|4|5|6|7|1B|8|@]|9|@$A|1C|B|1D|1|1E]]|C|$]]|$1|D|3|E|5|6|7|1F|8|@]|9|@$A|1G|B|1H|1|1I]|$A|1J|B|1K|1|1L]]|C|$]]|$1|F|3|G|5|6|7|1M|8|@]|9|@$A|1N|B|1O|1|1P]]|C|$]]|$1|H|3|I|5|J|7|1Q|8|@]|9|@$A|1R|B|1S|1|1T]]|C|$]]|$1|K|3|L|5|6|7|1U|8|@]|9|@]|C|$]]|$1|M|3|N|5|J|7|1V|8|@]|9|@$A|1W|B|1X|1|1Y]]|C|$]]|$1|O|3|P|5|6|7|1Z|8|@]|9|@]|C|$]]|$1|Q|3|R|5|J|7|20|8|@]|9|@]|C|$]]|$1|S|3|-4|5|6|7|21|8|@]|9|@]|C|$]]|$1|T|3|-4|5|6|7|22|8|@]|9|@]|C|$]]]|U|$V|$5|W|X|Y|C|$Z|10]]|11|$5|W|X|Y|C|$Z|12]]|13|$5|W|X|Y|C|$Z|14]]|15|$5|W|X|Y|C|$Z|16]]|17|$5|W|X|Y|C|$Z|18]]|19|$5|W|X|Y|C|$Z|1A]]]]

For A+C) I think you should look at facets, they modify how objects are written as characters. You could store statistics here as well on how many times you streamed your objects.
Check out <a href="https://stackoverflow.com/questions/1096291/how-to-format-my-own-objects-when-using-stl-streams/">How to format my own objects when using STL streams?</a> for an example.

For B) You need to create your own streambuf and connect your ostream to that buffer (constructor argument). See <a href="https://stackoverflow.com/questions/524641/how-do-i-create-an-ostream-streambuf/528460#528460">Luc's links</a> + <a href="https://duckduckgo.com/?q=Deriving+new+streambuf+classes&amp;t=ffab&amp;ia=web" rel="nofollow noreferrer">Deriving new streambuf classes</a>.
In short you need to implement this for an ostream (minimum):

<ul>
<li>overflow (put a single char or flush buffer) (<a href="http://uw714doc.sco.com/en/SDK_clib/_overflow.html" rel="nofollow noreferrer">link</a>)</li>
<li>xsputn (put a char array to buffer)(<a href="http://www.cplusplus.com/reference/iostream/streambuf/xsputn/" rel="nofollow noreferrer">link</a>)</li>
<li>sync (<a href="http://uw714doc.sco.com/en/SDK_clib/_sync.html" rel="nofollow noreferrer">link</a>)</li>
</ul>

For educational purposes I want to create a ostream and stream buffer to do: 

<ol>
<li>fix endians when doing &lt;&lt; myVar; </li>
<li>store in a deque container instead of using std:cout or writing to a file </li>
<li>log extra data, such as how many times I did &lt;&lt;, how many times I did .write, the amount of bytes I written and how many times I flush(). But I do not need all the info.</li>
</ol>

I tried overloading but failed horribly. I tried overloading write by doing 

<pre><code>ostream&amp; write( const char* s, streamsize n ) 
</code></pre>

in my basic_stringstream2 class (I copied paste basic_stringstream into my cpp file and modified it) but the code kept using basic_ostream. I looked through code and it looks like I need to overload xsputn (which isn't mention on this page <a href="http://www.cplusplus.com/reference/iostream/ostream" rel="noreferrer">http://www.cplusplus.com/reference/iostream/ostream</a> ) but what else do I need to overload? and how do I construct my class (what does it need to inherit, etc)?

How do I create my own ostream/streambuf?

容器

出于教育目的，我想创建一个ostream和stream buffer来完成以下工作：修复执行<< myVar时的字节顺序；存储在双端容器中而不是使用std:cout或写入文件会记录额外的数据，例如我执行<<的次数、执行.write的次数、写入的字节数以及刷新的次数()。但我不需要所有的信息。我尝试了重载，但失败得很可怕...

问如何创建自己的ostream/streambuf？
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问如何创建自己的ostream/streambuf？
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