<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- qdiriterator.cpp --> <title>QDirIterator Class | Qt Core 5.12.6</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtcore-index.html">Qt Core</a></td><td ><a href="qtcore-module.html">C++ Classes</a></td><td >QDirIterator</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtcore-index.html">Qt 5.12.6 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"> <div class="toc"> <h3><a name="toc">Contents</a></h3> <ul> <li class="level1"><a href="#public-types">Public Types</a></li> <li class="level1"><a href="#public-functions">Public Functions</a></li> <li class="level1"><a href="#details">Detailed Description</a></li> </ul> </div> <div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">QDirIterator Class</h1> <!-- $$$QDirIterator-brief --> <p>The <a href="qdiriterator.html">QDirIterator</a> class provides an iterator for directory entrylists. <a href="#details">More...</a></p> <!-- @@@QDirIterator --> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QDirIterator></span> </td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += core</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> Qt 4.3</td></tr></table></div><ul> <li><a href="qdiriterator-members.html">List of all members, including inherited members</a></li> </ul> <a name="public-types"></a> <h2 id="public-types">Public Types</h2> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> enum </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#IteratorFlag-enum">IteratorFlag</a></b> { NoIteratorFlags, Subdirectories, FollowSymlinks }</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> flags </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#IteratorFlag-enum">IteratorFlags</a></b></td></tr> </table></div> <a name="public-functions"></a> <h2 id="public-functions">Public Functions</h2> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#QDirIterator">QDirIterator</a></b>(const QDir &<i>dir</i>, QDirIterator::IteratorFlags <i>flags</i> = NoIteratorFlags)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#QDirIterator-1">QDirIterator</a></b>(const QString &<i>path</i>, QDirIterator::IteratorFlags <i>flags</i> = NoIteratorFlags)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#QDirIterator-2">QDirIterator</a></b>(const QString &<i>path</i>, QDir::Filters <i>filters</i>, QDirIterator::IteratorFlags <i>flags</i> = NoIteratorFlags)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#QDirIterator-3">QDirIterator</a></b>(const QString &<i>path</i>, const QStringList &<i>nameFilters</i>, QDir::Filters <i>filters</i> = QDir::NoFilter, QDirIterator::IteratorFlags <i>flags</i> = NoIteratorFlags)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#dtor.QDirIterator">~QDirIterator</a></b>()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QFileInfo </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#fileInfo">fileInfo</a></b>() const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QString </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#fileName">fileName</a></b>() const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QString </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#filePath">filePath</a></b>() const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#hasNext">hasNext</a></b>() const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QString </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#next">next</a></b>()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QString </td><td class="memItemRight bottomAlign"><b><a href="qdiriterator.html#path">path</a></b>() const</td></tr> </table></div> <a name="details"></a> <!-- $$$QDirIterator-description --> <div class="descr"> <h2 id="details">Detailed Description</h2> <p>The <a href="qdiriterator.html">QDirIterator</a> class provides an iterator for directory entrylists.</p> <p>You can use <a href="qdiriterator.html">QDirIterator</a> to navigate entries of a directory one at a time. It is similar to <a href="qdir.html#entryList">QDir::entryList</a>() and <a href="qdir.html#entryInfoList">QDir::entryInfoList</a>(), but because it lists entries one at a time instead of all at once, it scales better and is more suitable for large directories. It also supports listing directory contents recursively, and following symbolic links. Unlike <a href="qdir.html#entryList">QDir::entryList</a>(), <a href="qdiriterator.html">QDirIterator</a> does not support sorting.</p> <p>The <a href="qdiriterator.html">QDirIterator</a> constructor takes a <a href="qdir.html">QDir</a> or a directory as argument. After construction, the iterator is located before the first directory entry. Here's how to iterate over all the entries sequentially:</p> <pre class="cpp"> <span class="type"><a href="qdiriterator.html#QDirIterator">QDirIterator</a></span> it(<span class="string">"/etc"</span><span class="operator">,</span> <span class="type"><a href="qdiriterator.html#QDirIterator">QDirIterator</a></span><span class="operator">::</span>Subdirectories); <span class="keyword">while</span> (it<span class="operator">.</span>hasNext()) { <a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator"><</span><span class="operator"><</span> it<span class="operator">.</span>next(); <span class="comment">// /etc/.</span> <span class="comment">// /etc/..</span> <span class="comment">// /etc/X11</span> <span class="comment">// /etc/X11/fs</span> <span class="comment">// ...</span> } </pre> <p>Here's how to find and read all files filtered by name, recursively:</p> <pre class="cpp"> <span class="type"><a href="qdiriterator.html#QDirIterator">QDirIterator</a></span> it(<span class="string">"/sys"</span><span class="operator">,</span> <span class="type"><a href="qstringlist.html">QStringList</a></span>() <span class="operator"><</span><span class="operator"><</span> <span class="string">"scaling_cur_freq"</span><span class="operator">,</span> <span class="type"><a href="qdir.html">QDir</a></span><span class="operator">::</span>NoFilter<span class="operator">,</span> <span class="type"><a href="qdiriterator.html#QDirIterator">QDirIterator</a></span><span class="operator">::</span>Subdirectories); <span class="keyword">while</span> (it<span class="operator">.</span>hasNext()) { <span class="type"><a href="qfile.html">QFile</a></span> f(it<span class="operator">.</span>next()); f<span class="operator">.</span>open(<span class="type"><a href="qiodevice.html">QIODevice</a></span><span class="operator">::</span>ReadOnly); <a href="qtglobal.html#qDebug">qDebug</a>() <span class="operator"><</span><span class="operator"><</span> f<span class="operator">.</span>fileName() <span class="operator"><</span><span class="operator"><</span> f<span class="operator">.</span>readAll()<span class="operator">.</span>trimmed()<span class="operator">.</span>toDouble() <span class="operator">/</span> <span class="number">1000</span> <span class="operator"><</span><span class="operator"><</span> <span class="string">"MHz"</span>; } </pre> <p>The <a href="qdiriterator.html#next">next</a>() function returns the path to the next directory entry and advances the iterator. You can also call <a href="qdiriterator.html#filePath">filePath</a>() to get the current file path without advancing the iterator. The <a href="qdiriterator.html#fileName">fileName</a>() function returns only the name of the file, similar to how <a href="qdir.html#entryList">QDir::entryList</a>() works. You can also call <a href="qdiriterator.html#fileInfo">fileInfo</a>() to get a <a href="qfileinfo.html">QFileInfo</a> for the current entry.</p> <p>Unlike Qt's container iterators, <a href="qdiriterator.html">QDirIterator</a> is uni-directional (i.e., you cannot iterate directories in reverse order) and does not allow random access.</p> </div> <p><b>See also </b><a href="qdir.html">QDir</a> and <a href="qdir.html#entryList">QDir::entryList</a>().</p> <!-- @@@QDirIterator --> <div class="types"> <h2>Member Type Documentation</h2> <!-- $$$IteratorFlag$$$NoIteratorFlags$$$FollowSymlinks$$$Subdirectories --> <h3 class="flags" id="IteratorFlag-enum"><a name="IteratorFlag-enum"></a>enum QDirIterator::<span class="name">IteratorFlag</span><br/>flags QDirIterator::<span class="name">IteratorFlags</span></h3> <p>This enum describes flags that you can combine to configure the behavior of <a href="qdiriterator.html">QDirIterator</a>.</p> <div class="table"><table class="valuelist"><tr valign="top" class="odd"><th class="tblConst">Constant</th><th class="tblval">Value</th><th class="tbldscr">Description</th></tr> <tr><td class="topAlign"><code>QDirIterator::NoIteratorFlags</code></td><td class="topAlign tblval"><code>0x0</code></td><td class="topAlign">The default value, representing no flags. The iterator will return entries for the assigned path.</td></tr> <tr><td class="topAlign"><code>QDirIterator::Subdirectories</code></td><td class="topAlign tblval"><code>0x2</code></td><td class="topAlign">List entries inside all subdirectories as well.</td></tr> <tr><td class="topAlign"><code>QDirIterator::FollowSymlinks</code></td><td class="topAlign tblval"><code>0x1</code></td><td class="topAlign">When combined with Subdirectories, this flag enables iterating through all subdirectories of the assigned path, following all symbolic links. Symbolic link loops (e.g., "link" => "." or "link" => "..") are automatically detected and ignored.</td></tr> </table></div> <p>The IteratorFlags type is a typedef for <a href="qflags.html">QFlags</a><IteratorFlag>. It stores an OR combination of IteratorFlag values.</p> <!-- @@@IteratorFlag --> </div> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$QDirIterator[overload1]$$$QDirIteratorconstQDir&QDirIterator::IteratorFlags --> <h3 class="fn" id="QDirIterator"><a name="QDirIterator"></a>QDirIterator::<span class="name">QDirIterator</span>(const <span class="type"><a href="qdir.html">QDir</a></span> &<i>dir</i>, <span class="type"><a href="qdiriterator.html#IteratorFlag-enum">QDirIterator::IteratorFlags</a></span> <i>flags</i> = NoIteratorFlags)</h3> <p>Constructs a <a href="qdiriterator.html">QDirIterator</a> that can iterate over <i>dir</i>'s entrylist, using <i>dir</i>'s name filters and regular filters. You can pass options via <i>flags</i> to decide how the directory should be iterated.</p> <p>By default, <i>flags</i> is <a href="qdiriterator.html#IteratorFlag-enum">NoIteratorFlags</a>, which provides the same behavior as in <a href="qdir.html#entryList">QDir::entryList</a>().</p> <p>The sorting in <i>dir</i> is ignored.</p> <p><b>Note: </b>To list symlinks that point to non existing files, <a href="qdir.html#Filter-enum">QDir::System</a> must be passed to the flags.</p><p><b>See also </b><a href="qdiriterator.html#hasNext">hasNext</a>(), <a href="qdiriterator.html#next">next</a>(), and <a href="qdiriterator.html#IteratorFlag-enum">IteratorFlags</a>.</p> <!-- @@@QDirIterator --> <!-- $$$QDirIterator$$$QDirIteratorconstQString&QDirIterator::IteratorFlags --> <h3 class="fn" id="QDirIterator-1"><a name="QDirIterator-1"></a>QDirIterator::<span class="name">QDirIterator</span>(const <span class="type"><a href="qstring.html">QString</a></span> &<i>path</i>, <span class="type"><a href="qdiriterator.html#IteratorFlag-enum">QDirIterator::IteratorFlags</a></span> <i>flags</i> = NoIteratorFlags)</h3> <p>Constructs a <a href="qdiriterator.html">QDirIterator</a> that can iterate over <i>path</i>. You can pass options via <i>flags</i> to decide how the directory should be iterated.</p> <p>By default, <i>flags</i> is <a href="qdiriterator.html#IteratorFlag-enum">NoIteratorFlags</a>, which provides the same behavior as in <a href="qdir.html#entryList">QDir::entryList</a>().</p> <p><b>Note: </b>To list symlinks that point to non existing files, <a href="qdir.html#Filter-enum">QDir::System</a> must be passed to the flags.</p><p><b>See also </b><a href="qdiriterator.html#hasNext">hasNext</a>(), <a href="qdiriterator.html#next">next</a>(), and <a href="qdiriterator.html#IteratorFlag-enum">IteratorFlags</a>.</p> <!-- @@@QDirIterator --> <!-- $$$QDirIterator$$$QDirIteratorconstQString&QDir::FiltersQDirIterator::IteratorFlags --> <h3 class="fn" id="QDirIterator-2"><a name="QDirIterator-2"></a>QDirIterator::<span class="name">QDirIterator</span>(const <span class="type"><a href="qstring.html">QString</a></span> &<i>path</i>, <span class="type"><a href="qdir.html#Filter-enum">QDir::Filters</a></span> <i>filters</i>, <span class="type"><a href="qdiriterator.html#IteratorFlag-enum">QDirIterator::IteratorFlags</a></span> <i>flags</i> = NoIteratorFlags)</h3> <p>Constructs a <a href="qdiriterator.html">QDirIterator</a> that can iterate over <i>path</i>, with no name filtering and <i>filters</i> for entry filtering. You can pass options via <i>flags</i> to decide how the directory should be iterated.</p> <p>By default, <i>filters</i> is <a href="qdir.html#Filter-enum">QDir::NoFilter</a>, and <i>flags</i> is <a href="qdiriterator.html#IteratorFlag-enum">NoIteratorFlags</a>, which provides the same behavior as in <a href="qdir.html#entryList">QDir::entryList</a>().</p> <p><b>Note: </b>To list symlinks that point to non existing files, <a href="qdir.html#Filter-enum">QDir::System</a> must be passed to the flags.</p><p><b>See also </b><a href="qdiriterator.html#hasNext">hasNext</a>(), <a href="qdiriterator.html#next">next</a>(), and <a href="qdiriterator.html#IteratorFlag-enum">IteratorFlags</a>.</p> <!-- @@@QDirIterator --> <!-- $$$QDirIterator$$$QDirIteratorconstQString&constQStringList&QDir::FiltersQDirIterator::IteratorFlags --> <h3 class="fn" id="QDirIterator-3"><a name="QDirIterator-3"></a>QDirIterator::<span class="name">QDirIterator</span>(const <span class="type"><a href="qstring.html">QString</a></span> &<i>path</i>, const <span class="type"><a href="qstringlist.html">QStringList</a></span> &<i>nameFilters</i>, <span class="type"><a href="qdir.html#Filter-enum">QDir::Filters</a></span> <i>filters</i> = QDir::NoFilter, <span class="type"><a href="qdiriterator.html#IteratorFlag-enum">QDirIterator::IteratorFlags</a></span> <i>flags</i> = NoIteratorFlags)</h3> <p>Constructs a <a href="qdiriterator.html">QDirIterator</a> that can iterate over <i>path</i>, using <i>nameFilters</i> and <i>filters</i>. You can pass options via <i>flags</i> to decide how the directory should be iterated.</p> <p>By default, <i>flags</i> is <a href="qdiriterator.html#IteratorFlag-enum">NoIteratorFlags</a>, which provides the same behavior as <a href="qdir.html#entryList">QDir::entryList</a>().</p> <p><b>Note: </b>To list symlinks that point to non existing files, <a href="qdir.html#Filter-enum">QDir::System</a> must be passed to the flags.</p><p><b>See also </b><a href="qdiriterator.html#hasNext">hasNext</a>(), <a href="qdiriterator.html#next">next</a>(), and <a href="qdiriterator.html#IteratorFlag-enum">IteratorFlags</a>.</p> <!-- @@@QDirIterator --> <!-- $$$~QDirIterator[overload1]$$$~QDirIterator --> <h3 class="fn" id="dtor.QDirIterator"><a name="dtor.QDirIterator"></a>QDirIterator::<span class="name">~QDirIterator</span>()</h3> <p>Destroys the <a href="qdiriterator.html">QDirIterator</a>.</p> <!-- @@@~QDirIterator --> <!-- $$$fileInfo[overload1]$$$fileInfo --> <h3 class="fn" id="fileInfo"><a name="fileInfo"></a><span class="type"><a href="qfileinfo.html">QFileInfo</a></span> QDirIterator::<span class="name">fileInfo</span>() const</h3> <p>Returns a <a href="qfileinfo.html">QFileInfo</a> for the current directory entry.</p> <p><b>See also </b><a href="qdiriterator.html#filePath">filePath</a>() and <a href="qdiriterator.html#fileName">fileName</a>().</p> <!-- @@@fileInfo --> <!-- $$$fileName[overload1]$$$fileName --> <h3 class="fn" id="fileName"><a name="fileName"></a><span class="type"><a href="qstring.html">QString</a></span> QDirIterator::<span class="name">fileName</span>() const</h3> <p>Returns the file name for the current directory entry, without the path prepended.</p> <p>This function is convenient when iterating a single directory. When using the <a href="qdiriterator.html#IteratorFlag-enum">QDirIterator::Subdirectories</a> flag, you can use <a href="qdiriterator.html#filePath">filePath</a>() to get the full path.</p> <p><b>See also </b><a href="qdiriterator.html#filePath">filePath</a>() and <a href="qdiriterator.html#fileInfo">fileInfo</a>().</p> <!-- @@@fileName --> <!-- $$$filePath[overload1]$$$filePath --> <h3 class="fn" id="filePath"><a name="filePath"></a><span class="type"><a href="qstring.html">QString</a></span> QDirIterator::<span class="name">filePath</span>() const</h3> <p>Returns the full file path for the current directory entry.</p> <p><b>See also </b><a href="qdiriterator.html#fileInfo">fileInfo</a>() and <a href="qdiriterator.html#fileName">fileName</a>().</p> <!-- @@@filePath --> <!-- $$$hasNext[overload1]$$$hasNext --> <h3 class="fn" id="hasNext"><a name="hasNext"></a><span class="type">bool</span> QDirIterator::<span class="name">hasNext</span>() const</h3> <p>Returns <code>true</code> if there is at least one more entry in the directory; otherwise, false is returned.</p> <p><b>See also </b><a href="qdiriterator.html#next">next</a>(), <a href="qdiriterator.html#fileName">fileName</a>(), <a href="qdiriterator.html#filePath">filePath</a>(), and <a href="qdiriterator.html#fileInfo">fileInfo</a>().</p> <!-- @@@hasNext --> <!-- $$$next[overload1]$$$next --> <h3 class="fn" id="next"><a name="next"></a><span class="type"><a href="qstring.html">QString</a></span> QDirIterator::<span class="name">next</span>()</h3> <p>Advances the iterator to the next entry, and returns the file path of this new entry. If <a href="qdiriterator.html#hasNext">hasNext</a>() returns <code>false</code>, this function does nothing, and returns an empty <a href="qstring.html">QString</a>.</p> <p>You can call <a href="qdiriterator.html#fileName">fileName</a>() or <a href="qdiriterator.html#filePath">filePath</a>() to get the current entry file name or path, or <a href="qdiriterator.html#fileInfo">fileInfo</a>() to get a <a href="qfileinfo.html">QFileInfo</a> for the current entry.</p> <p><b>See also </b><a href="qdiriterator.html#hasNext">hasNext</a>(), <a href="qdiriterator.html#fileName">fileName</a>(), <a href="qdiriterator.html#filePath">filePath</a>(), and <a href="qdiriterator.html#fileInfo">fileInfo</a>().</p> <!-- @@@next --> <!-- $$$path[overload1]$$$path --> <h3 class="fn" id="path"><a name="path"></a><span class="type"><a href="qstring.html">QString</a></span> QDirIterator::<span class="name">path</span>() const</h3> <p>Returns the base directory of the iterator.</p> <!-- @@@path --> </div> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>