1<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 2<html xmlns="http://www.w3.org/1999/xhtml"> 3<head> 4<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/> 5<meta http-equiv="X-UA-Compatible" content="IE=9"/> 6<meta name="generator" content="Doxygen 1.8.6"/> 7<title>Boost.Locale: Frequently Asked Questions</title> 8<link href="tabs.css" rel="stylesheet" type="text/css"/> 9<script type="text/javascript" src="jquery.js"></script> 10<script type="text/javascript" src="dynsections.js"></script> 11<link href="navtree.css" rel="stylesheet" type="text/css"/> 12<script type="text/javascript" src="resize.js"></script> 13<script type="text/javascript" src="navtree.js"></script> 14<script type="text/javascript"> 15 $(document).ready(initResizable); 16 $(window).load(resizeHeight); 17</script> 18<link href="doxygen.css" rel="stylesheet" type="text/css" /> 19</head> 20<body> 21<div id="top"><!-- do not remove this div, it is closed by doxygen! --> 22<div id="titlearea"> 23<table cellspacing="0" cellpadding="0"> 24 <tbody> 25 <tr style="height: 56px;"> 26 <td id="projectlogo"><img alt="Logo" src="boost-small.png"/></td> 27 <td style="padding-left: 0.5em;"> 28 <div id="projectname">Boost.Locale 29 </div> 30 </td> 31 </tr> 32 </tbody> 33</table> 34</div> 35<!-- end header part --> 36<!-- Generated by Doxygen 1.8.6 --> 37 <div id="navrow1" class="tabs"> 38 <ul class="tablist"> 39 <li><a href="index.html"><span>Main Page</span></a></li> 40 <li class="current"><a href="pages.html"><span>Related Pages</span></a></li> 41 <li><a href="modules.html"><span>Modules</span></a></li> 42 <li><a href="namespaces.html"><span>Namespaces</span></a></li> 43 <li><a href="annotated.html"><span>Classes</span></a></li> 44 <li><a href="files.html"><span>Files</span></a></li> 45 <li><a href="examples.html"><span>Examples</span></a></li> 46 </ul> 47 </div> 48</div><!-- top --> 49<div id="side-nav" class="ui-resizable side-nav-resizable"> 50 <div id="nav-tree"> 51 <div id="nav-tree-contents"> 52 <div id="nav-sync" class="sync"></div> 53 </div> 54 </div> 55 <div id="splitbar" style="-moz-user-select:none;" 56 class="ui-resizable-handle"> 57 </div> 58</div> 59<script type="text/javascript"> 60$(document).ready(function(){initNavTree('faq.html','');}); 61</script> 62<div id="doc-content"> 63<div class="header"> 64 <div class="headertitle"> 65<div class="title">Frequently Asked Questions </div> </div> 66</div><!--header--> 67<div class="contents"> 68<div class="textblock"><ul> 69<li><a class="anchor" id="faq_bad_cast"></a><b>I try to use some Boost.Locale functions and I get an <code>std::bad_cast</code> exception thrown?</b> <br/> 70 <br/> 71 <b>Answer:</b> You probably try to use incorrect <code>std::locale</code> object. All Boost.Locale tools relay on <code>std::locale</code> object's facets. The locale object should be generated with <a class="el" href="classboost_1_1locale_1_1generator.html">generator</a> class and then passed to the function or alternatively global locale should be set using <code>std::locale::global()</code> function such that global locale (and default created one) would have required facets to use.</li> 72<li><a class="anchor" id="faq_number"></a><b>I had installed global locale and try to write something to stream but still get wrong output?</b> For example: <div class="fragment"><div class="line"><span class="preprocessor">#include <boost/locale.hpp></span></div> 73<div class="line"><span class="preprocessor">#include <iostream></span></div> 74<div class="line"><span class="keywordtype">int</span> main()</div> 75<div class="line">{</div> 76<div class="line"> <a class="code" href="classboost_1_1locale_1_1generator.html">boost::locale::generator</a> gen;</div> 77<div class="line"> std::locale::global(gen(<span class="stringliteral">""</span>));</div> 78<div class="line"> std::cout << <a class="code" href="group__manipulators.html#gae05b82e6658dc573521518fed5f5c77f">boost::locale::as::date</a> << <a class="code" href="group__manipulators.html#gae669b101cbeaed6f6d246ebdcaa8f39c">std::time</a>(0) << std::endl;</div> 79<div class="line">}</div> 80</div><!-- fragment --> Prints a number instead of a date. <br/> 81 <b>Answer:</b> You forget to imbue the locale to the stream. Changing the global locale does not affect the locale in existing <code>iostream</code> objects. Thus because <code>std::out</code> and other global streams were created before changing the global locale Boost.Locale manipulators have no effect. You need to write: <div class="fragment"><div class="line"><span class="preprocessor">#include <boost/locale.hpp></span></div> 82<div class="line"><span class="preprocessor">#include <iostream></span></div> 83<div class="line"><span class="keywordtype">int</span> main()</div> 84<div class="line">{</div> 85<div class="line"> <a class="code" href="classboost_1_1locale_1_1generator.html">boost::locale::generator</a> gen;</div> 86<div class="line"> std::locale l = gen(<span class="stringliteral">""</span>);</div> 87<div class="line"> std::locale::global(l);</div> 88<div class="line"> std::cout.imbue(l);</div> 89<div class="line"> std::cout << <a class="code" href="group__manipulators.html#gae05b82e6658dc573521518fed5f5c77f">boost::locale::as::date</a> << <a class="code" href="group__manipulators.html#gae669b101cbeaed6f6d246ebdcaa8f39c">std::time</a>(0) << std::endl;</div> 90<div class="line">}</div> 91</div><!-- fragment --> </li> 92</ul> 93</div></div><!-- contents --> 94</div><!-- doc-content --> 95 96 <li class="footer"> 97© Copyright 2009-2012 Artyom Beilis, Distributed under the <a href="http://www.boost.org/LICENSE_1_0.txt">Boost Software License</a>, Version 1.0. 98 </li> 99 </ul> 100 </div> 101</body> 102</html> 103
