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<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QStringList Class Reference</h1>
<p>The QStringList class provides a list of strings.
<a href="#details">More...</a>
<p>All the functions in this class are <a href="threads.html#reentrant">reentrant</a> when Qt is built with thread support.</p>
<p><tt>#include &lt;<a href="qstringlist-h.html">qstringlist.h</a>&gt;</tt>
<p>Inherits <a href="qvaluelist.html">QValueList</a>&lt;QString&gt;.
<p><a href="qstringlist-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li class=fn><a href="#QStringList"><b>QStringList</b></a> ()</li>
<li class=fn><a href="#QStringList-2"><b>QStringList</b></a> ( const&nbsp;QStringList&nbsp;&amp;&nbsp;l )</li>
<li class=fn><a href="#QStringList-3"><b>QStringList</b></a> ( const&nbsp;QValueList&lt;QString&gt;&nbsp;&amp;&nbsp;l )</li>
<li class=fn><a href="#QStringList-4"><b>QStringList</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;i )</li>
<li class=fn><a href="#QStringList-5"><b>QStringList</b></a> ( const&nbsp;char&nbsp;*&nbsp;i )</li>
<li class=fn>void <a href="#sort"><b>sort</b></a> ()</li>
<li class=fn>QString <a href="#join"><b>join</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;sep ) const</li>
<li class=fn>QStringList <a href="#grep"><b>grep</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;str, bool&nbsp;cs = TRUE ) const</li>
<li class=fn>QStringList <a href="#grep-2"><b>grep</b></a> ( const&nbsp;QRegExp&nbsp;&amp;&nbsp;rx ) const</li>
<li class=fn>QStringList &amp; <a href="#gres"><b>gres</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;before, const&nbsp;QString&nbsp;&amp;&nbsp;after, bool&nbsp;cs = TRUE )</li>
<li class=fn>QStringList &amp; <a href="#gres-2"><b>gres</b></a> ( const&nbsp;QRegExp&nbsp;&amp;&nbsp;rx, const&nbsp;QString&nbsp;&amp;&nbsp;after )</li>
</ul>
<h2>Static Public Members</h2>
<ul>
<li class=fn>QStringList <a href="#fromStrList"><b>fromStrList</b></a> ( const&nbsp;QStrList&nbsp;&amp;&nbsp;ascii )</li>
<li class=fn>QStringList <a href="#split-2"><b>split</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;sep, const&nbsp;QString&nbsp;&amp;&nbsp;str, bool&nbsp;allowEmptyEntries = FALSE )</li>
<li class=fn>QStringList <a href="#split-3"><b>split</b></a> ( const&nbsp;QChar&nbsp;&amp;&nbsp;sep, const&nbsp;QString&nbsp;&amp;&nbsp;str, bool&nbsp;allowEmptyEntries = FALSE )</li>
<li class=fn>QStringList <a href="#split"><b>split</b></a> ( const&nbsp;QRegExp&nbsp;&amp;&nbsp;sep, const&nbsp;QString&nbsp;&amp;&nbsp;str, bool&nbsp;allowEmptyEntries = FALSE )</li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
The QStringList class provides a list of strings.
<p>
<p> It is used to store and manipulate strings that logically belong
together. Essentially QStringList is a <a href="qvaluelist.html">QValueList</a> of <a href="qstring.html">QString</a>
objects. Unlike <a href="qstrlist.html">QStrList</a>, which stores pointers to characters,
QStringList holds real QString objects. It is the class of choice
whenever you work with Unicode strings. QStringList is part of the
<a href="qtl.html">Qt Template Library</a>.
<p> Like QString itself, QStringList objects are <a href="shclass.html#implicitly-shared">implicitly shared</a>, so
passing them around as value-parameters is both fast and safe.
<p> Strings can be added to a list using <a href="qvaluelist.html#append">append</a>(), <a href="qvaluelist.html#operator+-eq">operator+=</a>() or
<a href="qvaluelist.html#operator-lt-lt">operator&lt;&lt;</a>(), e.g.
<pre>
QStringList fonts;
fonts.<a href="qvaluelist.html#append">append</a>( "Times" );
fonts += "Courier";
fonts += "Courier New";
fonts &lt;&lt; "Helvetica [Cronyx]" &lt;&lt; "Helvetica [Adobe]";
</pre>
<p> String lists have an iterator, QStringList::Iterator(), e.g.
<pre>
for ( QStringList::<a href="qvaluelist.html#Iterator">Iterator</a> it = fonts.begin(); it != fonts.end(); ++it ) {
cout &lt;&lt; *it &lt;&lt; ":";
}
cout &lt;&lt; endl;
// Output:
// Times:Courier:Courier New:Helvetica [Cronyx]:Helvetica [Adobe]:
</pre>
<p> Many Qt functions return string lists by value; to iterate over
these you should make a copy and iterate over the copy.
<p> You can concatenate all the strings in a string list into a single
string (with an optional separator) using <a href="#join">join</a>(), e.g.
<pre>
<a href="qstring.html">QString</a> allFonts = fonts.join( ", " );
cout &lt;&lt; allFonts &lt;&lt; endl;
// Output:
// Times, Courier, Courier New, Helvetica [Cronyx], Helvetica [Adobe]
</pre>
<p> You can sort the list with <a href="#sort">sort</a>(), and extract a new list which
contains only those strings which contain a particular substring
(or match a particular <a href="qregexp.html#regular-expression">regular expression</a>) using the <a href="#grep">grep</a>()
functions, e.g.
<pre>
fonts.sort();
cout &lt;&lt; fonts.join( ", " ) &lt;&lt; endl;
// Output:
// Courier, Courier New, Helvetica [Adobe], Helvetica [Cronyx], Times
QStringList helveticas = fonts.grep( "Helvetica" );
cout &lt;&lt; helveticas.<a href="#join">join</a>( ", " ) &lt;&lt; endl;
// Output:
// Helvetica [Adobe], Helvetica [Cronyx]
</pre>
<p> Existing strings can be split into string lists with character,
string or regular expression separators, e.g.
<pre>
<a href="qstring.html">QString</a> s = "Red\tGreen\tBlue";
QStringList colors = QStringList::<a href="#split">split</a>( "\t", s );
cout &lt;&lt; colors.<a href="#join">join</a>( ", " ) &lt;&lt; endl;
// Output:
// Red, Green, Blue
</pre>
<p>See also <a href="shared.html">Implicitly and Explicitly Shared Classes</a>, <a href="text.html">Text Related Classes</a>, and <a href="tools.html">Non-GUI Classes</a>.
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="QStringList"></a>QStringList::QStringList ()
</h3>
<p> Creates an empty string list.
<h3 class=fn><a name="QStringList-2"></a>QStringList::QStringList ( const&nbsp;<a href="qstringlist.html">QStringList</a>&nbsp;&amp;&nbsp;l )
</h3>
<p> Creates a copy of the list <em>l</em>. This function is very fast
because QStringList is <a href="shclass.html#implicitly-shared">implicitly shared</a>. In most situations this
acts like a <a href="shclass.html#deep-copy">deep copy</a>, for example, if this list or the original
one or some other list referencing the same shared data is
modified, the modifying list first makes a copy, i.e.
copy-on-write.
In a threaded environment you may require a real deep copy
.
<h3 class=fn><a name="QStringList-3"></a>QStringList::QStringList ( const&nbsp;<a href="qvaluelist.html">QValueList</a>&lt;QString&gt;&nbsp;&amp;&nbsp;l )
</h3>
<p> Constructs a new string list that is a copy of <em>l</em>.
<h3 class=fn><a name="QStringList-4"></a>QStringList::QStringList ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;i )
</h3>
<p> Constructs a string list consisting of the single string <em>i</em>.
Longer lists are easily created as follows:
<p> <pre>
QStringList items;
items &lt;&lt; "Buy" &lt;&lt; "Sell" &lt;&lt; "Update" &lt;&lt; "Value";
</pre>
<h3 class=fn><a name="QStringList-5"></a>QStringList::QStringList ( const&nbsp;char&nbsp;*&nbsp;i )
</h3>
<p> Constructs a string list consisting of the single Latin-1 string <em>i</em>.
<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="fromStrList"></a>QStringList::fromStrList ( const&nbsp;<a href="qstrlist.html">QStrList</a>&nbsp;&amp;&nbsp;ascii )<tt> [static]</tt>
</h3>
Converts from an ASCII-QStrList <em>ascii</em> to a QStringList (Unicode).
<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="grep"></a>QStringList::grep ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;str, bool&nbsp;cs = TRUE ) const
</h3>
Returns a list of all the strings containing the substring <em>str</em>.
<p> If <em>cs</em> is TRUE, the grep is done case-sensitively; otherwise
case is ignored.
<p> <pre>
QStringList list;
list &lt;&lt; "Bill Gates" &lt;&lt; "John Doe" &lt;&lt; "Bill Clinton";
list = list.<a href="#grep">grep</a>( "Bill" );
// list == ["Bill Gates", "Bill Clinton"]
</pre>
<p> <p>See also <a href="qstring.html#find">QString::find</a>().
<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="grep-2"></a>QStringList::grep ( const&nbsp;<a href="qregexp.html">QRegExp</a>&nbsp;&amp;&nbsp;rx ) const
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Returns a list of all the strings that match the <a href="qregexp.html#regular-expression">regular expression</a> <em>rx</em>.
<p> <p>See also <a href="qstring.html#find">QString::find</a>().
<h3 class=fn><a href="qstringlist.html">QStringList</a>&nbsp;&amp; <a name="gres"></a>QStringList::gres ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;before, const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;after, bool&nbsp;cs = TRUE )
</h3>
Replaces every occurrence of the string <em>before</em> in the strings
that constitute the string list with the string <em>after</em>. Returns
a reference to the string list.
<p> If <em>cs</em> is TRUE, the search is case sensitive; otherwise the
search is case insensitive.
<p> Example:
<pre>
QStringList list;
list &lt;&lt; "alpha" &lt;&lt; "beta" &lt;&lt; "gamma" &lt;&lt; "epsilon";
list.<a href="#gres">gres</a>( "a", "o" );
// list == ["olpho", "beto", "gommo", "epsilon"]
</pre>
<p> <p>See also <a href="qstring.html#replace">QString::replace</a>().
<h3 class=fn><a href="qstringlist.html">QStringList</a>&nbsp;&amp; <a name="gres-2"></a>QStringList::gres ( const&nbsp;<a href="qregexp.html">QRegExp</a>&nbsp;&amp;&nbsp;rx, const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;after )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Replaces every occurrence of the regexp <em>rx</em> in the string
with <em>after</em>. Returns a reference to the string list.
<p> Example:
<pre>
QStringList list;
list &lt;&lt; "alpha" &lt;&lt; "beta" &lt;&lt; "gamma" &lt;&lt; "epsilon";
list.<a href="#gres">gres</a>( QRegExp("^a"), "o" );
// list == ["olpha", "beta", "gamma", "epsilon"]
</pre>
<p> For regexps containing <a href="qregexp.html#capturing-text">capturing parentheses</a>, occurrences of <b>&#92;1</b>,
<b>&#92;2</b>, ..., in <em>after</em> are replaced with <em>rx</em>.cap(1),
cap(2), ...
<p> Example:
<pre>
QStringList list;
list &lt;&lt; "Bill Clinton" &lt;&lt; "Gates, Bill";
list.<a href="#gres">gres</a>( QRegExp("^(.*), (.*)$"), "\\2 \\1" );
// list == ["Bill Clinton", "Bill Gates"]
</pre>
<p> <p>See also <a href="qstring.html#replace">QString::replace</a>().
<h3 class=fn><a href="qstring.html">QString</a> <a name="join"></a>QStringList::join ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;sep ) const
</h3>
Joins the string list into a single string with each element
separated by the string <em>sep</em> (which can be empty).
<p> <p>See also <a href="#split">split</a>().
<p>Examples: <a href="fileiconview-example.html#x872">fileiconview/qfileiconview.cpp</a> and <a href="toplevel-example.html#x2533">toplevel/options.ui.h</a>.
<h3 class=fn>void <a name="sort"></a>QStringList::sort ()
</h3>
Sorts the list of strings in ascending case-sensitive order.
<p> Sorting is very fast. It uses the <a href="qtl.html">Qt Template
Library's</a> efficient HeapSort implementation that has a
time complexity of O(n*log n).
<p> If you want to sort your strings in an arbitrary order consider
using a <a href="qmap.html">QMap</a>. For example you could use a QMap&lt;QString,QString&gt;
to create a case-insensitive ordering (e.g. mapping the lowercase
text to the text), or a QMap&lt;int,QString&gt; to sort the strings by
some integer index, etc.
<p>Example: <a href="themes-example.html#x341">themes/themes.cpp</a>.
<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="split"></a>QStringList::split ( const&nbsp;<a href="qregexp.html">QRegExp</a>&nbsp;&amp;&nbsp;sep, const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;str, bool&nbsp;allowEmptyEntries = FALSE )<tt> [static]</tt>
</h3>
Splits the string <em>str</em> into strings wherever the <a href="qregexp.html#regular-expression">regular expression</a> <em>sep</em> occurs, and returns the list of those strings.
<p> If <em>allowEmptyEntries</em> is TRUE, a null string is inserted in
the list wherever the separator matches twice without intervening
text.
<p> For example, if you split the string "a,,b,c" on commas, <a href="#split">split</a>()
returns the three-item list "a", "b", "c" if <em>allowEmptyEntries</em>
is FALSE (the default), and the four-item list "a", "", "b", "c"
if <em>allowEmptyEntries</em> is TRUE.
<p> If <em>sep</em> does not match anywhere in <em>str</em>, split() returns a
single element list with the element containing the single string
<em>str</em>.
<p> <p>See also <a href="#join">join</a>() and <a href="qstring.html#section">QString::section</a>().
<p>Examples: <a href="tutorial2-03.html#x2552">chart/element.cpp</a>, <a href="dirview-example.html#x1703">dirview/dirview.cpp</a>, and <a href="httpd-example.html#x733">network/httpd/httpd.cpp</a>.
<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="split-2"></a>QStringList::split ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;sep, const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;str, bool&nbsp;allowEmptyEntries = FALSE )<tt> [static]</tt>
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> This version of the function uses a <a href="qstring.html">QString</a> as separator, rather
than a <a href="qregexp.html#regular-expression">regular expression</a>.
<p> If <em>sep</em> is an empty string, the return value is a list of
one-character strings: <a href="#split">split</a>( QString( "" ), "four" ) returns the
four-item list, "f", "o", "u", "r".
<p> If <em>allowEmptyEntries</em> is TRUE, a null string is inserted in
the list wherever the separator matches twice without intervening
text.
<p> <p>See also <a href="#join">join</a>() and <a href="qstring.html#section">QString::section</a>().
<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="split-3"></a>QStringList::split ( const&nbsp;<a href="qchar.html">QChar</a>&nbsp;&amp;&nbsp;sep, const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;str, bool&nbsp;allowEmptyEntries = FALSE )<tt> [static]</tt>
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> This version of the function uses a <a href="qchar.html">QChar</a> as separator, rather
than a <a href="qregexp.html#regular-expression">regular expression</a>.
<p> <p>See also <a href="#join">join</a>() and <a href="qstring.html#section">QString::section</a>().
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