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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>QAsciiDict Class Reference</h1>
<p>The QAsciiDict class is a template class that provides a dictionary based on char* keys.
<a href="#details">More...</a>
<p><tt>#include &lt;<a href="qasciidict-h.html">qasciidict.h</a>&gt;</tt>
<p>Inherits <a href="qptrcollection.html">QPtrCollection</a>.
<p><a href="qasciidict-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li class=fn><a href="#QAsciiDict"><b>QAsciiDict</b></a> ( int&nbsp;size = 17, bool&nbsp;caseSensitive = TRUE, bool&nbsp;copyKeys = TRUE )</li>
<li class=fn><a href="#QAsciiDict-2"><b>QAsciiDict</b></a> ( const&nbsp;QAsciiDict&lt;type&gt;&nbsp;&amp;&nbsp;dict )</li>
<li class=fn><a href="#~QAsciiDict"><b>~QAsciiDict</b></a> ()</li>
<li class=fn>QAsciiDict&lt;type&gt; &amp; <a href="#operator-eq"><b>operator=</b></a> ( const&nbsp;QAsciiDict&lt;type&gt;&nbsp;&amp;&nbsp;dict )</li>
<li class=fn>virtual uint <a href="#count"><b>count</b></a> () const</li>
<li class=fn>uint <a href="#size"><b>size</b></a> () const</li>
<li class=fn>bool <a href="#isEmpty"><b>isEmpty</b></a> () const</li>
<li class=fn>void <a href="#insert"><b>insert</b></a> ( const&nbsp;char&nbsp;*&nbsp;key, const&nbsp;type&nbsp;*&nbsp;item )</li>
<li class=fn>void <a href="#replace"><b>replace</b></a> ( const&nbsp;char&nbsp;*&nbsp;key, const&nbsp;type&nbsp;*&nbsp;item )</li>
<li class=fn>bool <a href="#remove"><b>remove</b></a> ( const&nbsp;char&nbsp;*&nbsp;key )</li>
<li class=fn>type * <a href="#take"><b>take</b></a> ( const&nbsp;char&nbsp;*&nbsp;key )</li>
<li class=fn>type * <a href="#find"><b>find</b></a> ( const&nbsp;char&nbsp;*&nbsp;key ) const</li>
<li class=fn>type * <a href="#operator[]"><b>operator[]</b></a> ( const&nbsp;char&nbsp;*&nbsp;key ) const</li>
<li class=fn>virtual void <a href="#clear"><b>clear</b></a> ()</li>
<li class=fn>void <a href="#resize"><b>resize</b></a> ( uint&nbsp;newsize )</li>
<li class=fn>void <a href="#statistics"><b>statistics</b></a> () const</li>
</ul>
<h2>Important Inherited Members</h2>
<ul>
<li class=fn>bool <a href="#autoDelete"><b>autoDelete</b></a> () const</li>
<li class=fn>void <a href="#setAutoDelete"><b>setAutoDelete</b></a> ( bool&nbsp;enable )</li>
</ul>
<h2>Protected Members</h2>
<ul>
<li class=fn>virtual QDataStream &amp; <a href="#read"><b>read</b></a> ( QDataStream&nbsp;&amp;&nbsp;s, QPtrCollection::Item&nbsp;&amp;&nbsp;item )</li>
<li class=fn>virtual QDataStream &amp; <a href="#write"><b>write</b></a> ( QDataStream&nbsp;&amp;&nbsp;s, QPtrCollection::Item ) const</li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
The QAsciiDict class is a template class that provides a dictionary based on char* keys.
<p>
<p>
<p> QAsciiDict is implemented as a template class. Define a template
instance QAsciiDict&lt;X&gt; to create a dictionary that operates on
pointers to X (X*).
<p> A dictionary is a collection of key-value pairs. The key is a
char* used for insertion, removal and lookup. The value is a
pointer. Dictionaries provide very fast insertion and lookup.
<p> QAsciiDict cannot handle Unicode keys; use the <a href="qdict.html">QDict</a> template
instead, which uses <a href="qstring.html">QString</a> keys. A QDict has the same
performace as a QAsciiDict.
<p> Example:
<pre>
QAsciiDict&lt;QLineEdit&gt; fields; // char* keys, QLineEdit* values
fields.<a href="#insert">insert</a>( "forename", new <a href="qlineedit.html">QLineEdit</a>( this ) );
fields.<a href="#insert">insert</a>( "surname", new <a href="qlineedit.html">QLineEdit</a>( this ) );
fields["forename"]-&gt;setText( "Homer" );
fields["surname"]-&gt;setText( "Simpson" );
<a href="qasciidictiterator.html">QAsciiDictIterator</a>&lt;QLineEdit&gt; it( fields ); // See QAsciiDictIterator
for( ; it.<a href="qasciidictiterator.html#current">current</a>(); ++it )
cout &lt;&lt; it.<a href="qasciidictiterator.html#currentKey">currentKey</a>() &lt;&lt; ": " &lt;&lt; it.<a href="qasciidictiterator.html#current">current</a>()-&gt;text() &lt;&lt; endl;
cout &lt;&lt; endl;
if ( fields["forename"] &amp;&amp; fields["surname"] )
cout &lt;&lt; fields["forename"]-&gt;text() &lt;&lt; " "
&lt;&lt; fields["surname"]-&gt;text() &lt;&lt; endl; // Prints "Homer Simpson"
fields.<a href="#remove">remove</a>( "forename" ); // Does not delete the line edit
if ( ! fields["forename"] )
cout &lt;&lt; "forename is not in the dictionary" &lt;&lt; endl;
</pre>
In this example we use a dictionary to keep track of the line
edits we're using. We insert each line edit into the dictionary
with a unique name and then access the line edits via the
dictionary. See <a href="qptrdict.html">QPtrDict</a>, <a href="qintdict.html">QIntDict</a> and <a href="qdict.html">QDict</a>.
<p> See QDict for full details, including the choice of dictionary
size, and how deletions are handled.
<p> <p>See also <a href="qasciidictiterator.html">QAsciiDictIterator</a>, <a href="qdict.html">QDict</a>, <a href="qintdict.html">QIntDict</a>, <a href="qptrdict.html">QPtrDict</a>, <a href="collection.html">Collection Classes</a>, <a href="collection.html">Collection Classes</a>, and <a href="tools.html">Non-GUI Classes</a>.
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="QAsciiDict"></a>QAsciiDict::QAsciiDict ( int&nbsp;size = 17, bool&nbsp;caseSensitive = TRUE, bool&nbsp;copyKeys = TRUE )
</h3>
<p> Constructs a dictionary optimized for less than <em>size</em> entries.
<p> We recommend setting <em>size</em> to a suitably large <a href="primes.html#prime">prime</a> number (a
bit larger than the expected number of entries). This makes the
hash distribution better and will improve lookup performance.
<p> When <em>caseSensitive</em> is TRUE (the default) QAsciiDict treats
"abc" and "Abc" as different keys; when it is FALSE "abc" and
"Abc" are the same. Case-insensitive comparison only considers the
26 letters in US-ASCII.
<p> If <em>copyKeys</em> is TRUE (the default), the dictionary copies keys
using strcpy(); if it is FALSE, the dictionary just copies the
pointers.
<h3 class=fn><a name="QAsciiDict-2"></a>QAsciiDict::QAsciiDict ( const&nbsp;<a href="qasciidict.html">QAsciiDict</a>&lt;type&gt;&nbsp;&amp;&nbsp;dict )
</h3>
<p> Constructs a copy of <em>dict</em>.
<p> Each item in <em>dict</em> is inserted into this dictionary. Only the
pointers are copied (shallow copy).
<h3 class=fn><a name="~QAsciiDict"></a>QAsciiDict::~QAsciiDict ()
</h3>
<p> Removes all items from the dictionary and destroys it.
<p> The items are deleted if auto-delete is enabled.
<p> All iterators that access this dictionary will be reset.
<p> <p>See also <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>().
<h3 class=fn>bool <a name="autoDelete"></a>QPtrCollection::autoDelete () const
</h3>
<p> Returns the setting of the auto-delete option. The default is FALSE.
<p> <p>See also <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>().
<h3 class=fn>void <a name="clear"></a>QAsciiDict::clear ()<tt> [virtual]</tt>
</h3>
<p> Removes all items from the dictionary.
<p> The removed items are deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
<p> All dictionary iterators that operate on dictionary are reset.
<p> <p>See also <a href="#remove">remove</a>(), <a href="#take">take</a>(), and <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>().
<p>Reimplemented from <a href="qptrcollection.html#clear">QPtrCollection</a>.
<h3 class=fn>uint <a name="count"></a>QAsciiDict::count () const<tt> [virtual]</tt>
</h3>
<p> Returns the number of items in the dictionary.
<p> <p>See also <a href="#isEmpty">isEmpty</a>().
<p>Reimplemented from <a href="qptrcollection.html#count">QPtrCollection</a>.
<h3 class=fn>type * <a name="find"></a>QAsciiDict::find ( const&nbsp;char&nbsp;*&nbsp;key ) const
</h3>
<p> Returns the item associated with <em>key</em>, or 0 if the key does not
exist in the dictionary.
<p> This function uses an internal hashing algorithm to optimize
lookup.
<p> If there are two or more items with equal keys, then the item that
was most recently inserted will be found.
<p> Equivalent to the [] operator.
<p> <p>See also <a href="#operator[]">operator[]</a>().
<h3 class=fn>void <a name="insert"></a>QAsciiDict::insert ( const&nbsp;char&nbsp;*&nbsp;key, const&nbsp;type&nbsp;*&nbsp;item )
</h3>
<p> Inserts the <em>key</em> with the <em>item</em> into the dictionary.
<p> Multiple items can have the same key, in which case only the last
item will be accessible using <a href="#operator[]">operator[]</a>().
<p> <em>item</em> may not be 0.
<p> <p>See also <a href="#replace">replace</a>().
<h3 class=fn>bool <a name="isEmpty"></a>QAsciiDict::isEmpty () const
</h3>
<p> Returns TRUE if the dictionary is empty, i.e. <a href="#count">count</a>() == 0;
otherwise it returns FALSE.
<p> <p>See also <a href="#count">count</a>().
<h3 class=fn><a href="qasciidict.html">QAsciiDict</a>&lt;type&gt;&nbsp;&amp; <a name="operator-eq"></a>QAsciiDict::operator= ( const&nbsp;<a href="qasciidict.html">QAsciiDict</a>&lt;type&gt;&nbsp;&amp;&nbsp;dict )
</h3>
<p> Assigns <em>dict</em> to this dictionary and returns a reference to this
dictionary.
<p> This dictionary is first cleared and then each item in <em>dict</em> is
inserted into this dictionary. Only the pointers are copied
(shallow copy) unless <a href="qptrcollection.html#newItem">newItem</a>() has been reimplemented().
<h3 class=fn>type * <a name="operator[]"></a>QAsciiDict::operator[] ( const&nbsp;char&nbsp;*&nbsp;key ) const
</h3>
<p> Returns the item associated with <em>key</em>, or 0 if the key does
not exist in the dictionary.
<p> This function uses an internal hashing algorithm to optimize
lookup.
<p> If there are two or more items with equal keys, then the item that
was most recently inserted will be found.
<p> Equivalent to the <a href="#find">find</a>() function.
<p> <p>See also <a href="#find">find</a>().
<h3 class=fn><a href="qdatastream.html">QDataStream</a>&nbsp;&amp; <a name="read"></a>QAsciiDict::read ( <a href="qdatastream.html">QDataStream</a>&nbsp;&amp;&nbsp;s, <a href="qptrcollection.html#Item">QPtrCollection::Item</a>&nbsp;&amp;&nbsp;item )<tt> [virtual protected]</tt>
</h3>
<p> Reads a dictionary item from the stream <em>s</em> and returns a
reference to the stream.
<p> The default implementation sets <em>item</em> to 0.
<p> <p>See also <a href="#write">write</a>().
<h3 class=fn>bool <a name="remove"></a>QAsciiDict::remove ( const&nbsp;char&nbsp;*&nbsp;key )
</h3>
<p> Removes the item associated with <em>key</em> from the dictionary.
Returns TRUE if successful, i.e. if the key existed in the
dictionary; otherwise returns FALSE.
<p> If there are two or more items with equal keys, then the most
recently inserted item will be removed.
<p> The removed item is deleted if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled.
<p> All dictionary iterators that refer to the removed item will be
set to point to the next item in the dictionary traversal order.
<p> <p>See also <a href="#take">take</a>(), <a href="#clear">clear</a>(), and <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>().
<h3 class=fn>void <a name="replace"></a>QAsciiDict::replace ( const&nbsp;char&nbsp;*&nbsp;key, const&nbsp;type&nbsp;*&nbsp;item )
</h3>
<p> Replaces an item that has a key equal to <em>key</em> with <em>item</em>.
<p> If the item does not already exist, it will be inserted.
<p> <em>item</em> may not be 0.
<p> Equivalent to:
<pre>
QAsciiDict&lt;char&gt; dict;
...
if ( dict.<a href="#find">find</a>(key) )
dict.<a href="#remove">remove</a>( key );
dict.<a href="#insert">insert</a>( key, item );
</pre>
<p> If there are two or more items with equal keys, then the most
recently inserted item will be replaced.
<p> <p>See also <a href="#insert">insert</a>().
<h3 class=fn>void <a name="resize"></a>QAsciiDict::resize ( uint&nbsp;newsize )
</h3>
<p> Changes the size of the hashtable to <em>newsize</em>. The contents of
the dictionary are preserved but all iterators on the dictionary
become invalid.
<h3 class=fn>void <a name="setAutoDelete"></a>QPtrCollection::setAutoDelete ( bool&nbsp;enable )
</h3>
<p> Sets the collection to auto-delete its contents if <em>enable</em> is
TRUE and to never delete them if <em>enable</em> is FALSE.
<p> If auto-deleting is turned on, all the items in a collection are
deleted when the collection itself is deleted. This is convenient
if the collection has the only pointer to the items.
<p> The default setting is FALSE, for safety. If you turn it on, be
careful about copying the collection - you might find yourself
with two collections deleting the same items.
<p> Note that the auto-delete setting may also affect other functions
in subclasses. For example, a subclass that has a <a href="#remove">remove</a>()
function will remove the item from its data structure, and if
auto-delete is enabled, will also delete the item.
<p> <p>See also <a href="qptrcollection.html#autoDelete">autoDelete</a>().
<p>Examples: <a href="grapher-nsplugin-example.html#x2769">grapher/grapher.cpp</a>, <a href="scribble-example.html#x924">scribble/scribble.cpp</a>, and <a href="bigtable-example.html#x1291">table/bigtable/main.cpp</a>.
<h3 class=fn>uint <a name="size"></a>QAsciiDict::size () const
</h3>
<p> Returns the size of the internal hash array (as specified in the
constructor).
<p> <p>See also <a href="#count">count</a>().
<h3 class=fn>void <a name="statistics"></a>QAsciiDict::statistics () const
</h3>
<p> Debugging-only function that prints out the dictionary
distribution using <a href="qapplication.html#qDebug">qDebug</a>().
<h3 class=fn>type * <a name="take"></a>QAsciiDict::take ( const&nbsp;char&nbsp;*&nbsp;key )
</h3>
<p> Takes the item associated with <em>key</em> out of the dictionary
without deleting it (even if <a href="qptrcollection.html#setAutoDelete">auto-deletion</a> is enabled).
<p> If there are two or more items with equal keys, then the most
recently inserted item will be taken.
<p> Returns a pointer to the item taken out, or 0 if the key does not
exist in the dictionary.
<p> All dictionary iterators that refer to the taken item will be set
to point to the next item in the dictionary traversal order.
<p> <p>See also <a href="#remove">remove</a>(), <a href="#clear">clear</a>(), and <a href="qptrcollection.html#setAutoDelete">setAutoDelete</a>().
<h3 class=fn><a href="qdatastream.html">QDataStream</a>&nbsp;&amp; <a name="write"></a>QAsciiDict::write ( <a href="qdatastream.html">QDataStream</a>&nbsp;&amp;&nbsp;s, <a href="qptrcollection.html#Item">QPtrCollection::Item</a> ) const<tt> [virtual protected]</tt>
</h3>
<p> Writes a dictionary item to the stream <em>s</em> and returns a
reference to the stream.
<p> <p>See also <a href="#read">read</a>().
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