<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<!-- qjsonarray.cpp -->
<title>const_iterator 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 >const_iterator</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="#public-variables">Public Variables</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">const_iterator Class</h1>
<span class="small-subtitle">(<a href="qjsonarray-const-iterator.html">QJsonArray::const_iterator</a>)<br/></span>
<!-- $$$const_iterator-brief -->
<p>The <a href="qjsonarray-const-iterator.html">QJsonArray::const_iterator</a> class provides an STL-style const iterator for <a href="qjsonarray.html">QJsonArray</a>. <a href="#details">More...</a></p>
<!-- @@@const_iterator -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <const_iterator></span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += core</td></tr></table></div><ul>
<li><a href="qjsonarray-const-iterator-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"> typedef </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#iterator_category-typedef">iterator_category</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="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#const_iterator-2">const_iterator</a></b>(const const_iterator &<i>other</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#const_iterator-3">const_iterator</a></b>(const iterator &<i>other</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-not-eq">operator!=</a></b>(const const_iterator &<i>other</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QJsonValue </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-2a">operator*</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-2b">operator+</a></b>(int <i>j</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator &</td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-2b-2b">operator++</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-2b-2b-1">operator++</a></b>(<i>int</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator &</td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-2b-eq">operator+=</a></b>(int <i>j</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-">operator-</a></b>(int <i>j</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator--1">operator-</a></b>(const_iterator <i>other</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator &</td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator--">operator--</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator---1">operator--</a></b>(<i>int</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const_iterator &</td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator--eq">operator-=</a></b>(int <i>j</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QJsonValue *</td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator--gt">operator-></a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-lt">operator<</a></b>(const const_iterator &<i>other</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-lt-eq">operator<=</a></b>(const const_iterator &<i>other</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-eq-eq">operator==</a></b>(const const_iterator &<i>other</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-gt">operator></a></b>(const const_iterator &<i>other</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-gt-eq">operator>=</a></b>(const const_iterator &<i>other</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QJsonValue </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#operator-5b-5d">operator[]</a></b>(int <i>j</i>) const</td></tr>
</table></div>
<a name="public-variables"></a>
<h2 id="public-variables">Public Variables</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> const QJsonArray *</td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#a-var">a</a></b></td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qjsonarray-const-iterator.html#i-var">i</a></b></td></tr>
</table></div>
<a name="details"></a>
<!-- $$$const_iterator-description -->
<div class="descr">
<h2 id="details">Detailed Description</h2>
<p>The <a href="qjsonarray-const-iterator.html">QJsonArray::const_iterator</a> class provides an STL-style const iterator for <a href="qjsonarray.html">QJsonArray</a>.</p>
<p><a href="qjsonarray-const-iterator.html">QJsonArray::const_iterator</a> allows you to iterate over a <a href="qjsonarray.html">QJsonArray</a>. If you want to modify the <a href="qjsonarray.html">QJsonArray</a> as you iterate over it, use <a href="qjsonarray-iterator.html">QJsonArray::iterator</a> instead. It is generally a good practice to use <a href="qjsonarray-const-iterator.html">QJsonArray::const_iterator</a> on a non-const <a href="qjsonarray.html">QJsonArray</a> as well, unless you need to change the <a href="qjsonarray.html">QJsonArray</a> through the iterator. Const iterators are slightly faster and improves code readability.</p>
<p>The default <a href="qjsonarray-const-iterator.html">QJsonArray::const_iterator</a> constructor creates an uninitialized iterator. You must initialize it using a <a href="qjsonarray.html">QJsonArray</a> function like <a href="qjsonarray.html#constBegin">QJsonArray::constBegin</a>(), <a href="qjsonarray.html#constEnd">QJsonArray::constEnd</a>(), or <a href="qjsonarray.html#insert">QJsonArray::insert</a>() before you can start iterating.</p>
<p>Most <a href="qjsonarray.html">QJsonArray</a> functions accept an integer index rather than an iterator. For that reason, iterators are rarely useful in connection with <a href="qjsonarray.html">QJsonArray</a>. One place where STL-style iterators do make sense is as arguments to <a href="qtalgorithms.html">generic algorithms</a>.</p>
<p>Multiple iterators can be used on the same array. However, be aware that any non-const function call performed on the <a href="qjsonarray.html">QJsonArray</a> will render all existing iterators undefined.</p>
</div>
<p><b>See also </b><a href="qjsonarray-iterator.html">QJsonArray::iterator</a>.</p>
<!-- @@@const_iterator -->
<div class="types">
<h2>Member Type Documentation</h2>
<!-- $$$iterator_category -->
<h3 class="fn" id="iterator_category-typedef"><a name="iterator_category-typedef"></a>typedef const_iterator::<span class="name">iterator_category</span></h3>
<p>A synonym for <i>std::random_access_iterator_tag</i> indicating this iterator is a random access iterator.</p>
<!-- @@@iterator_category -->
</div>
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$const_iterator[overload1]$$$const_iterator -->
<h3 class="fn" id="const_iterator"><a name="const_iterator"></a>const_iterator::<span class="name">const_iterator</span>()</h3>
<p>Constructs an uninitialized iterator.</p>
<p>Functions like operator*() and operator++() should not be called on an uninitialized iterator. Use operator=() to assign a value to it before using it.</p>
<p><b>See also </b><a href="qjsonarray.html#constBegin">QJsonArray::constBegin</a>() and <a href="qjsonarray.html#constEnd">QJsonArray::constEnd</a>().</p>
<!-- @@@const_iterator -->
<!-- $$$const_iterator$$$const_iteratorconstconst_iterator& -->
<h3 class="fn" id="const_iterator-2"><a name="const_iterator-2"></a>const_iterator::<span class="name">const_iterator</span>(const <span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &<i>other</i>)</h3>
<p>Constructs a copy of <i>other</i>.</p>
<!-- @@@const_iterator -->
<!-- $$$const_iterator$$$const_iteratorconstiterator& -->
<h3 class="fn" id="const_iterator-3"><a name="const_iterator-3"></a>const_iterator::<span class="name">const_iterator</span>(const <span class="type"><a href="qjsonarray-iterator.html">iterator</a></span> &<i>other</i>)</h3>
<p>Constructs a copy of <i>other</i>.</p>
<!-- @@@const_iterator -->
<!-- $$$operator!=[overload1]$$$operator!=constconst_iterator& -->
<h3 class="fn" id="operator-not-eq"><a name="operator-not-eq"></a><span class="type">bool</span> const_iterator::<span class="name">operator!=</span>(const <span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &<i>other</i>) const</h3>
<p>Returns <code>true</code> if <i>other</i> points to a different item than this iterator; otherwise returns <code>false</code>.</p>
<p><b>See also </b><a href="qjsonarray-const-iterator.html#operator-eq-eq">operator==</a>().</p>
<!-- @@@operator!= -->
<!-- $$$operator*[overload1]$$$operator* -->
<h3 class="fn" id="operator-2a"><a name="operator-2a"></a><span class="type"><a href="qjsonvalue.html">QJsonValue</a></span> const_iterator::<span class="name">operator*</span>() const</h3>
<p>Returns the current item.</p>
<!-- @@@operator* -->
<!-- $$$operator+[overload1]$$$operator+int -->
<h3 class="fn" id="operator-2b"><a name="operator-2b"></a><span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> const_iterator::<span class="name">operator+</span>(<span class="type">int</span> <i>j</i>) const</h3>
<p>Returns an iterator to the item at <i>j</i> positions forward from this iterator. If <i>j</i> is negative, the iterator goes backward.</p>
<p><b>See also </b><a href="qjsonarray-const-iterator.html#operator-">operator-</a>() and <a href="qjsonarray-const-iterator.html#operator-2b-eq">operator+=</a>().</p>
<!-- @@@operator+ -->
<!-- $$$operator++[overload1]$$$operator++ -->
<h3 class="fn" id="operator-2b-2b"><a name="operator-2b-2b"></a><span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &const_iterator::<span class="name">operator++</span>()</h3>
<p>The prefix ++ operator, <code>++it</code>, advances the iterator to the next item in the array and returns an iterator to the new current item.</p>
<p>Calling this function on <a href="qjsonarray.html#end">QJsonArray::end</a>() leads to undefined results.</p>
<p><b>See also </b><a href="qjsonarray-const-iterator.html#operator--">operator--</a>().</p>
<!-- @@@operator++ -->
<!-- $$$operator++$$$operator++int -->
<h3 class="fn" id="operator-2b-2b-1"><a name="operator-2b-2b-1"></a><span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> const_iterator::<span class="name">operator++</span>(<i>int</i>)</h3>
<p>This is an overloaded function.</p>
<p>The postfix ++ operator, <code>it++</code>, advances the iterator to the next item in the array and returns an iterator to the previously current item.</p>
<!-- @@@operator++ -->
<!-- $$$operator+=[overload1]$$$operator+=int -->
<h3 class="fn" id="operator-2b-eq"><a name="operator-2b-eq"></a><span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &const_iterator::<span class="name">operator+=</span>(<span class="type">int</span> <i>j</i>)</h3>
<p>Advances the iterator by <i>j</i> items. If <i>j</i> is negative, the iterator goes backward.</p>
<p><b>See also </b><a href="qjsonarray-const-iterator.html#operator--eq">operator-=</a>() and <a href="qjsonarray-const-iterator.html#operator-2b">operator+</a>().</p>
<!-- @@@operator+= -->
<!-- $$$operator-[overload1]$$$operator-int -->
<h3 class="fn" id="operator-"><a name="operator-"></a><span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> const_iterator::<span class="name">operator-</span>(<span class="type">int</span> <i>j</i>) const</h3>
<p>Returns an iterator to the item at <i>j</i> positions backward from this iterator. If <i>j</i> is negative, the iterator goes forward.</p>
<p><b>See also </b><a href="qjsonarray-const-iterator.html#operator-2b">operator+</a>() and <a href="qjsonarray-const-iterator.html#operator--eq">operator-=</a>().</p>
<!-- @@@operator- -->
<!-- $$$operator-$$$operator-const_iterator -->
<h3 class="fn" id="operator--1"><a name="operator--1"></a><span class="type">int</span> const_iterator::<span class="name">operator-</span>(<span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> <i>other</i>) const</h3>
<p>Returns the number of items between the item pointed to by <i>other</i> and the item pointed to by this iterator.</p>
<!-- @@@operator- -->
<!-- $$$operator--[overload1]$$$operator-- -->
<h3 class="fn" id="operator--"><a name="operator--"></a><span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &const_iterator::<span class="name">operator--</span>()</h3>
<p>The prefix -- operator, <code>--it</code>, makes the preceding item current and returns an iterator to the new current item.</p>
<p>Calling this function on <a href="qjsonarray.html#begin">QJsonArray::begin</a>() leads to undefined results.</p>
<p><b>See also </b><a href="qjsonarray-const-iterator.html#operator-2b-2b">operator++</a>().</p>
<!-- @@@operator-- -->
<!-- $$$operator--$$$operator--int -->
<h3 class="fn" id="operator---1"><a name="operator---1"></a><span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> const_iterator::<span class="name">operator--</span>(<i>int</i>)</h3>
<p>This is an overloaded function.</p>
<p>The postfix -- operator, <code>it--</code>, makes the preceding item current and returns an iterator to the previously current item.</p>
<!-- @@@operator-- -->
<!-- $$$operator-=[overload1]$$$operator-=int -->
<h3 class="fn" id="operator--eq"><a name="operator--eq"></a><span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &const_iterator::<span class="name">operator-=</span>(<span class="type">int</span> <i>j</i>)</h3>
<p>Makes the iterator go back by <i>j</i> items. If <i>j</i> is negative, the iterator goes forward.</p>
<p><b>See also </b><a href="qjsonarray-const-iterator.html#operator-2b-eq">operator+=</a>() and <a href="qjsonarray-const-iterator.html#operator-">operator-</a>().</p>
<!-- @@@operator-= -->
<!-- $$$operator->[overload1]$$$operator-> -->
<h3 class="fn" id="operator--gt"><a name="operator--gt"></a><span class="type"><a href="qjsonvalue.html">QJsonValue</a></span> *const_iterator::<span class="name">operator-></span>() const</h3>
<p>Returns a pointer to the current item.</p>
<!-- @@@operator-> -->
<!-- $$$operator<[overload1]$$$operator<constconst_iterator& -->
<h3 class="fn" id="operator-lt"><a name="operator-lt"></a><span class="type">bool</span> const_iterator::<span class="name">operator<</span>(const <span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &<i>other</i>) const</h3>
<p>Returns <code>true</code> if the item pointed to by this iterator is less than the item pointed to by the <i>other</i> iterator.</p>
<!-- @@@operator< -->
<!-- $$$operator<=[overload1]$$$operator<=constconst_iterator& -->
<h3 class="fn" id="operator-lt-eq"><a name="operator-lt-eq"></a><span class="type">bool</span> const_iterator::<span class="name">operator<=</span>(const <span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &<i>other</i>) const</h3>
<p>Returns <code>true</code> if the item pointed to by this iterator is less than or equal to the item pointed to by the <i>other</i> iterator.</p>
<!-- @@@operator<= -->
<!-- $$$operator==[overload1]$$$operator==constconst_iterator& -->
<h3 class="fn" id="operator-eq-eq"><a name="operator-eq-eq"></a><span class="type">bool</span> const_iterator::<span class="name">operator==</span>(const <span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &<i>other</i>) const</h3>
<p>Returns <code>true</code> if <i>other</i> points to the same item as this iterator; otherwise returns <code>false</code>.</p>
<p><b>See also </b><a href="qjsonarray-const-iterator.html#operator-not-eq">operator!=</a>().</p>
<!-- @@@operator== -->
<!-- $$$operator>[overload1]$$$operator>constconst_iterator& -->
<h3 class="fn" id="operator-gt"><a name="operator-gt"></a><span class="type">bool</span> const_iterator::<span class="name">operator></span>(const <span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &<i>other</i>) const</h3>
<p>Returns <code>true</code> if the item pointed to by this iterator is greater than the item pointed to by the <i>other</i> iterator.</p>
<!-- @@@operator> -->
<!-- $$$operator>=[overload1]$$$operator>=constconst_iterator& -->
<h3 class="fn" id="operator-gt-eq"><a name="operator-gt-eq"></a><span class="type">bool</span> const_iterator::<span class="name">operator>=</span>(const <span class="type"><a href="qjsonarray-const-iterator.html#const_iterator">const_iterator</a></span> &<i>other</i>) const</h3>
<p>Returns <code>true</code> if the item pointed to by this iterator is greater than or equal to the item pointed to by the <i>other</i> iterator.</p>
<!-- @@@operator>= -->
<!-- $$$operator[][overload1]$$$operator[]int -->
<h3 class="fn" id="operator-5b-5d"><a name="operator-5b-5d"></a><span class="type"><a href="qjsonvalue.html">QJsonValue</a></span> const_iterator::<span class="name">operator[]</span>(<span class="type">int</span> <i>j</i>) const</h3>
<p>Returns the item at offset <i>j</i> from the item pointed to by this iterator (the item at position <code>*this + j</code>).</p>
<p>This function is provided to make <a href="qjsonarray.html">QJsonArray</a> iterators behave like C++ pointers.</p>
<p><b>See also </b><a href="qjsonarray-const-iterator.html#operator-2b">operator+</a>().</p>
<!-- @@@operator[] -->
</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>
distrib
>
Mageia
>
7
>
armv7hl
>
media
>
core-updates
>
by-pkgid
>
d5e62c01ae8d1e579463c6a871dd44bf
>
files
>
481
