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<td align="right" valign="top" width="230"><a href="http://www.trolltech.com"><img src="images/trolltech-logo.png" align="right" width="203" height="32" border="0" /></a></td></tr></table><h1 align="center">QLatin1String Class Reference<br /><sup><sup>[<a href="qtcore.html">QtCore</a> module]</sup></sup></h1>
<p>The QLatin1String class provides a thin wrapper around an ASCII/Latin-1 encoded string literal. <a href="#details">More...</a></p>
<pre> #include <QLatin1String></pre><p><b>Note:</b> All the functions in this class are <a href="threads.html#reentrant">reentrant</a>.</p>
<ul>
<li><a href="qlatin1string-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="public-functions"></a>
<h3>Public Functions</h3>
<ul>
<li><div class="fn"/><b><a href="qlatin1string.html#QLatin1String">QLatin1String</a></b> ( const char * <i>str</i> )</li>
<li><div class="fn"/>const char * <b><a href="qlatin1string.html#latin1">latin1</a></b> () const</li>
<li><div class="fn"/>bool <b><a href="qlatin1string.html#operator-not-eq">operator!=</a></b> ( const QString & <i>other</i> ) const</li>
<li><div class="fn"/>bool <b><a href="qlatin1string.html#operator-lt">operator<</a></b> ( const QString & <i>other</i> ) const</li>
<li><div class="fn"/>bool <b><a href="qlatin1string.html#operator-lt-eq">operator<=</a></b> ( const QString & <i>other</i> ) const</li>
<li><div class="fn"/>QLatin1String & <b><a href="qlatin1string.html#operator-eq">operator=</a></b> ( const QLatin1String & <i>other</i> )</li>
<li><div class="fn"/>bool <b><a href="qlatin1string.html#operator-eq-eq">operator==</a></b> ( const QString & <i>other</i> ) const</li>
<li><div class="fn"/>bool <b><a href="qlatin1string.html#operator-gt">operator></a></b> ( const QString & <i>other</i> ) const</li>
<li><div class="fn"/>bool <b><a href="qlatin1string.html#operator-gt-eq">operator>=</a></b> ( const QString & <i>other</i> ) const</li>
</ul>
<a name="details"></a>
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<h2>Detailed Description</h2>
<p>The QLatin1String class provides a thin wrapper around an ASCII/Latin-1 encoded string literal.</p>
<p>Many of <a href="qstring.html">QString</a>'s member functions are overloaded to accept <tt>const char *</tt> instead of <a href="qstring.html">QString</a>. This includes the copy constructor, the assignment operator, the comparison operators, and various other functions such as <a href="qstring.html#insert">insert()</a>, <a href="qstring.html#replace">replace()</a>, and <a href="qstring.html#indexOf">indexOf()</a>. These functions are usually optimized to avoid constructing a <a href="qstring.html">QString</a> object for the <tt>const char *</tt> data. For example, assuming <tt>str</tt> is a <a href="qstring.html">QString</a>,</p>
<pre> if (str == "auto" || str == "extern"
|| str == "static" || str == "register") {
...
}</pre>
<p>is much faster than</p>
<pre> if (str == QString("auto") || str == QString("extern")
|| str == QString("static") || str == QString("register")) {
...
}</pre>
<p>because it doesn't construct four temporary <a href="qstring.html">QString</a> objects and make a deep copy of the character data.</p>
<p>Applications that define <tt>QT_NO_CAST_FROM_ASCII</tt> (as explained in the <a href="qstring.html">QString</a> documentation) don't have access to <a href="qstring.html">QString</a>'s <tt>const char *</tt> API. To provide an efficient way of specifying constant Latin-1 strings, Qt provides the QLatin1String, which is just a very thin wrapper around a <tt>const char *</tt>. Using QLatin1String, the example code above becomes</p>
<pre> if (str == QLatin1String("auto")
|| str == QLatin1String("extern")
|| str == QLatin1String("static")
|| str == QLatin1String("register") {
...
}</pre>
<p>This is a bit longer to type, but it provides exactly the same benefits as the first version of the code, and is faster than converting the Latin-1 strings using <a href="qstring.html#fromLatin1">QString::fromLatin1</a>().</p>
<p>Thanks to the <a href="qstring.html">QString</a>(const QLatin1String &) constructor, QLatin1String can be used everywhere a <a href="qstring.html">QString</a> is expected. For example:</p>
<pre> QLabel *label = new QLabel(QLatin1String("MOD"), this);</pre>
<p>See also <a href="qstring.html">QString</a> and <a href="qlatin1char.html">QLatin1Char</a>.</p>
<hr />
<h2>Member Function Documentation</h2>
<h3 class="fn"><a name="QLatin1String"></a>QLatin1String::QLatin1String ( const char * <i>str</i> )</h3>
<p>Constructs a <a href="qlatin1string.html">QLatin1String</a> object that stores <i>str</i>.</p>
<p>The string data is <i>not</i> copied. The caller must be able to guarantee that <i>str</i> will not be deleted or modified as long as the <a href="qlatin1string.html">QLatin1String</a> object exists.</p>
<p>See also <a href="qlatin1string.html#latin1">latin1</a>().</p>
<h3 class="fn"><a name="latin1"></a>const char * QLatin1String::latin1 () const</h3>
<p>Returns the Latin-1 string stored in this object.</p>
<h3 class="fn"><a name="operator-not-eq"></a>bool QLatin1String::operator!= ( const <a href="qstring.html">QString</a> & <i>other</i> ) const</h3>
<p>Returns true if this string is not equal to string <i>other</i>; otherwise returns false.</p>
<p>The comparison is based exclusively on the numeric Unicode values of the characters and is very fast, but is not what a human would expect. Consider sorting user-interface strings with <a href="qstring.html#localeAwareCompare">QString::localeAwareCompare</a>().</p>
<h3 class="fn"><a name="operator-lt"></a>bool QLatin1String::operator< ( const <a href="qstring.html">QString</a> & <i>other</i> ) const</h3>
<p>Returns true if this string is lexically less than the <i>other</i> string; otherwise returns false.</p>
<p>The comparison is based exclusively on the numeric Unicode values of the characters and is very fast, but is not what a human would expect. Consider sorting user-interface strings using the <a href="qstring.html#localeAwareCompare">QString::localeAwareCompare</a>() function.</p>
<h3 class="fn"><a name="operator-lt-eq"></a>bool QLatin1String::operator<= ( const <a href="qstring.html">QString</a> & <i>other</i> ) const</h3>
<p>Returns true if this string is lexically less than or equal to string <i>other</i>; otherwise returns false.</p>
<p>The comparison is based exclusively on the numeric Unicode values of the characters and is very fast, but is not what a human would expect. Consider sorting user-interface strings with <a href="qstring.html#localeAwareCompare">QString::localeAwareCompare</a>().</p>
<h3 class="fn"><a name="operator-eq"></a>QLatin1String & QLatin1String::operator= ( const QLatin1String & <i>other</i> )</h3>
<p>Constructs a copy of <i>other</i>.</p>
<p>This function was introduced in Qt 4.1.</p>
<h3 class="fn"><a name="operator-eq-eq"></a>bool QLatin1String::operator== ( const <a href="qstring.html">QString</a> & <i>other</i> ) const</h3>
<p>Returns true if this string is equal to string <i>other</i>; otherwise returns false.</p>
<p>The comparison is based exclusively on the numeric Unicode values of the characters and is very fast, but is not what a human would expect. Consider sorting user-interface strings with <a href="qstring.html#localeAwareCompare">QString::localeAwareCompare</a>().</p>
<h3 class="fn"><a name="operator-gt"></a>bool QLatin1String::operator> ( const <a href="qstring.html">QString</a> & <i>other</i> ) const</h3>
<p>Returns true if this string is lexically greater than string <i>other</i>; otherwise returns false.</p>
<p>The comparison is based exclusively on the numeric Unicode values of the characters and is very fast, but is not what a human would expect. Consider sorting user-interface strings with <a href="qstring.html#localeAwareCompare">QString::localeAwareCompare</a>().</p>
<h3 class="fn"><a name="operator-gt-eq"></a>bool QLatin1String::operator>= ( const <a href="qstring.html">QString</a> & <i>other</i> ) const</h3>
<p>Returns true if this string is lexically greater than or equal to string <i>other</i>; otherwise returns false.</p>
<p>The comparison is based exclusively on the numeric Unicode values of the characters and is very fast, but is not what a human would expect. Consider sorting user-interface strings with <a href="qstring.html#localeAwareCompare">QString::localeAwareCompare</a>().</p>
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