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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>QMap Class Reference</h1>
<p>The QMap class is a value-based template class that provides
a dictionary.
<a href="#details">More...</a>
<p><tt>#include <<a href="qmap-h.html">qmap.h</a>></tt>
<p><a href="qmap-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li><div class=fn>typedef Key <a href="#key_type"><b>key_type</b></a></div></li>
<li><div class=fn>typedef T <a href="#mapped_type"><b>mapped_type</b></a></div></li>
<li><div class=fn>typedef QPair<const key_type, mapped_type> <a href="#value_type"><b>value_type</b></a></div></li>
<li><div class=fn>typedef value_type * <a href="#pointer"><b>pointer</b></a></div></li>
<li><div class=fn>typedef const value_type * <a href="#const_pointer"><b>const_pointer</b></a></div></li>
<li><div class=fn>typedef value_type & <a href="#reference"><b>reference</b></a></div></li>
<li><div class=fn>typedef const value_type & <a href="#const_reference"><b>const_reference</b></a></div></li>
<li><div class=fn>typedef size_t <a href="#size_type"><b>size_type</b></a></div></li>
<li><div class=fn>typedef QMapIterator<Key, T> <a href="#iterator"><b>iterator</b></a></div></li>
<li><div class=fn>typedef QMapConstIterator<Key, T> <a href="#const_iterator"><b>const_iterator</b></a></div></li>
<li><div class=fn><a href="#QMap"><b>QMap</b></a> ()</div></li>
<li><div class=fn><a href="#QMap-2"><b>QMap</b></a> ( const QMap<Key, T> & m )</div></li>
<li><div class=fn><a href="#QMap-3"><b>QMap</b></a> ( const std::map<Key, T> & m )</div></li>
<li><div class=fn><a href="#~QMap"><b>~QMap</b></a> ()</div></li>
<li><div class=fn>QMap<Key, T> & <a href="#operator-eq"><b>operator=</b></a> ( const QMap<Key, T> & m )</div></li>
<li><div class=fn>QMap<Key, T> & <a href="#operator-eq-2"><b>operator=</b></a> ( const std::map<Key, T> & m )</div></li>
<li><div class=fn>iterator <a href="#begin"><b>begin</b></a> ()</div></li>
<li><div class=fn>iterator <a href="#end"><b>end</b></a> ()</div></li>
<li><div class=fn>const_iterator <a href="#begin-2"><b>begin</b></a> () const</div></li>
<li><div class=fn>const_iterator <a href="#end-2"><b>end</b></a> () const</div></li>
<li><div class=fn>iterator <a href="#replace"><b>replace</b></a> ( const Key & k, const T & v )</div></li>
<li><div class=fn>size_type <a href="#size"><b>size</b></a> () const</div></li>
<li><div class=fn>bool <a href="#empty"><b>empty</b></a> () const</div></li>
<li><div class=fn>QPair<iterator, bool> <a href="#insert-2"><b>insert</b></a> ( const value_type & x )</div></li>
<li><div class=fn>void <a href="#erase"><b>erase</b></a> ( iterator it )</div></li>
<li><div class=fn>void <a href="#erase-2"><b>erase</b></a> ( const key_type & k )</div></li>
<li><div class=fn>size_type <a href="#count"><b>count</b></a> ( const key_type & k ) const</div></li>
<li><div class=fn>T & <a href="#operator[]"><b>operator[]</b></a> ( const Key & k )</div></li>
<li><div class=fn>void <a href="#clear"><b>clear</b></a> ()</div></li>
<li><div class=fn>typedef QMapIterator<Key, T> <a href="#Iterator"><b>Iterator</b></a></div></li>
<li><div class=fn>typedef QMapConstIterator<Key, T> <a href="#ConstIterator"><b>ConstIterator</b></a></div></li>
<li><div class=fn>typedef T <a href="#ValueType"><b>ValueType</b></a></div></li>
<li><div class=fn>iterator <a href="#find"><b>find</b></a> ( const Key & k )</div></li>
<li><div class=fn>const_iterator <a href="#find-2"><b>find</b></a> ( const Key & k ) const</div></li>
<li><div class=fn>const T & <a href="#operator[]-2"><b>operator[]</b></a> ( const Key & k ) const</div></li>
<li><div class=fn>bool <a href="#contains"><b>contains</b></a> ( const Key & k ) const</div></li>
<li><div class=fn>size_type <a href="#count-2"><b>count</b></a> () const</div></li>
<li><div class=fn>bool <a href="#isEmpty"><b>isEmpty</b></a> () const</div></li>
<li><div class=fn>iterator <a href="#insert"><b>insert</b></a> ( const Key & key, const T & value, bool overwrite = TRUE )</div></li>
<li><div class=fn>void <a href="#remove"><b>remove</b></a> ( iterator it )</div></li>
<li><div class=fn>void <a href="#remove-2"><b>remove</b></a> ( const Key & k )</div></li>
</ul>
<h2>Protected Members</h2>
<ul>
<li><div class=fn>void <a href="#detach"><b>detach</b></a> ()</div></li>
</ul>
<h2>Related Functions</h2>
<ul>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt"><b>operator>></b></a> ( QDataStream & s, QMap<Key, T> & m )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt"><b>operator<<</b></a> ( QDataStream & s, const QMap<Key, T> & m )</div></li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
<p> The QMap class is a value-based template class that provides
a dictionary.
<p>
<p> QMap is a Qt implementation of an STL-like map container. It
can be used in your application if the standard <tt>map</tt> is not
available. QMap is part of the <a href="qtl.html">Qt Template
Library</a>.
<p> QMap<Key, Data> defines a template instance to create a
dictionary with keys of type Key and values of type Data. QMap does
not store pointers to the members of the map; instead, it holds a
copy of every member. For that reason, QMap is value-based, whereas
<a href="qptrlist.html">QPtrList</a> and <a href="qdict.html">QDict</a> are pointer-based.
<p> QMap contains and manages a collection of objects of type Data with
associated key values of type Key and provides iterators that allow
the contained objects to be addressed. QMap owns the contained
items.
<p> Some classes cannot be used within a QMap. For example everything
derived from <a href="qobject.html">QObject</a> and thus all classes that implement widgets.
Only values can be used in a QMap. To qualify as a value, the class
must provide
<p> <ul>
<li> A copy constructor
<li> An assignment operator
<li> A default constructor, i.e. a constructor that does not take any arguments.
</ul>
<p> Note that C++ defaults to field-by-field assignment operators and
copy constructors if no explicit version is supplied. In many cases,
this is sufficient.
<p> The class used for the key requires that the <tt>operator<</tt> is implemented
to define ordering of the keys.
<p> QMap's function naming is consistent with the other Qt classes
(e.g., <a href="#count">count</a>(), <a href="#isEmpty">isEmpty</a>()). QMap also provides extra functions for
compatibility with STL algorithms, such as <a href="#size">size</a>() and <a href="#empty">empty</a>().
Programmers already familiar with the STL <tt>map</tt> can use these
functions instead.
<p> Example:
<a name="qmap-eg"></a>
<pre>
#include <<a href="qstring-h.html">qstring.h</a>>
#include <<a href="qmap-h.html">qmap.h</a>>
#include <<a href="qstring-h.html">qstring.h</a>>
class Employee
{
public:
Employee(): sn(0) {}
Employee( const <a href="qstring.html">QString</a>& forename, const <a href="qstring.html">QString</a>& surname, int salary )
: fn(forename), sn(surname), sal(salary)
{ }
<a href="qstring.html">QString</a> forename() const { return fn; }
<a href="qstring.html">QString</a> surname() const { return sn; }
int salary() const { return sal; }
void setSalary( int salary ) { sal = salary; }
private:
<a href="qstring.html">QString</a> fn;
<a href="qstring.html">QString</a> sn;
int sal;
};
int main(int argc, char **argv)
{
<a href="qapplication.html">QApplication</a> app( argc, argv );
typedef QMap<QString, Employee> EmployeeMap;
EmployeeMap map;
map["JD001"] = Employee("John", "Doe", 50000);
map["JD002"] = Employee("Jane", "Williams", 80000);
map["TJ001"] = Employee("Tom", "Jones", 60000);
Employee sasha( "Sasha", "Hind", 50000 );
map["SH001"] = sasha;
sasha.setSalary( 40000 );
EmployeeMap::<a href="#Iterator">Iterator</a> it;
for ( it = map.begin(); it != map.end(); ++it ) {
printf( "%s: %s, %s earns %d\n",
it.key().latin1(),
it.data().surname().latin1(),
it.data().forename().latin1(),
it.data().salary() );
}
return 0;
}
</pre>
<p> Program output:
<pre>
JD001: Doe, John earns 50000
JW002: Williams, Jane earns 80000
SH001: Hind, Sasha earns 50000
TJ001: Jones, Tom earns 60000
</pre>
<p> The latest changes to Sasha's salary did not affect the value in
the list because the map created a copy of Sasha's entry. In
addition, notice that the items are sorted alphabetically (by key)
when iterating over the map.
<p> There are several ways to find items in a map. The <a href="#begin">begin</a>() and
<a href="#end">end</a>() functions return iterators to the beginning and end of the
map. The advantage of using an iterator is that you can move
forward or backward by incrementing/decrementing the iterator. The
iterator returned by end() points to the element which is one past
the last element in the container. The past-the-end iterator is
still associated with the map it belongs to, however it is <em>not</em>
dereferenceable; <a href="qpoint.html#operator*-4">operator*</a>() will not return a well-defined value.
If the map is empty, the iterator returned by begin() will equal
the iterator returned by end().
<p> Another way to find an element in the map is by using the <a href="#find">find</a>()
function. This returns an iterator pointing to the desired
item or to the end() iterator if no such element exists.
<p> Another approach uses the operator[]. But be warned: if the map does
not contain an entry for the element you are looking for, operator[]
inserts a default value. If you do not know that the element you
are searching for is really in the list, you should not use
operator[]. The following example illustrates this:
<p> <pre>
QMap<QString,QString> map;
map["Clinton"] = "Bill";
str << map["Clinton"] << map["Bush"] << endl;
</pre>
<p> The code fragment will print out "Clinton", "". Since the value
associated with the "Bush" key did not exist, the map inserted a
default value (in this case, an empty string). If you are not
sure whether a certain element is in the map, you should use find()
and iterators instead.
<p> If you just want to know whether a certain key is contained in the
map, use the <a href="#contains">contains</a>() function. In addition, <a href="#count">count</a>() tells you how
many keys there are currently in the map.
<p> It is safe to have multiple iterators at the same time. If some
member of the map is removed, only iterators pointing to the removed
member become invalid; inserting in the map does not invalidate any
iterators.
<p> Since QMap is value-based, there is no need to be concerned about deleting
items in the map. The map holds its own copies and will free
them if the corresponding member or the map itself is deleted.
<p> QMap is <a href="shclass.html#implicitly-shared">implicitly shared</a>. This means you can just make copies of
the map in time O(1). If multiple QMap instances share the same data
and one is modifying the map's data, this modifying instance
makes a copy and modifies its private copy; it thus does not affect
other instances. From a developer's point of view you can think
that a QMap and a copy of this map have nothing to do with each
other. If a QMap is being used in a multi-threaded program, you must
protect all access to the map. See <a href="qmutex.html">QMutex</a>.
<p> There are several ways of inserting new items into the map. One
uses the <a href="#insert">insert</a>() method; the other one uses operator[] like this:
<pre>
QMap<QString, QString> map;
map["Clinton"] = "Bill";
map.<a href="#insert">insert</a>( qMakePair("Bush", "George") );
</pre>
<p> Items can also be removed from the map in several ways. The first is
to pass an iterator to <a href="#remove">remove</a>(). The other is to pass a key
value to remove(), which will delete the entry with the requested
key. In addition you can clear the entire map using the <a href="#clear">clear</a>()
method.
<p> <p>See also <a href="qmapiterator.html">QMapIterator</a>, <a href="qtl.html">Qt Template Library Classes</a>, <a href="shared.html">Implicitly and Explicitly Shared Classes</a> and <a href="tools.html">Non-GUI Classes</a>.
<hr><h2>Member Type Documentation</h2>
<h3 class=fn><a name="ConstIterator"></a>QMap::ConstIterator</h3>
The map's const iterator type, Qt style.
<h3 class=fn><a name="Iterator"></a>QMap::Iterator</h3>
The map's iterator type, Qt style.
<h3 class=fn><a name="ValueType"></a>QMap::ValueType</h3>
Corresponds to <a href="qpair.html">QPair</a><key_type, mapped_type>, Qt style.
<h3 class=fn><a name="const_iterator"></a>QMap::const_iterator</h3>
The map's const iterator type.
<h3 class=fn><a name="const_pointer"></a>QMap::const_pointer</h3>
Const pointer to value_type.
<h3 class=fn><a name="const_reference"></a>QMap::const_reference</h3>
Const reference to value_type.
<h3 class=fn><a name="iterator"></a>QMap::iterator</h3>
The map's iterator type.
<h3 class=fn><a name="key_type"></a>QMap::key_type</h3>
The map's key type.
<h3 class=fn><a name="mapped_type"></a>QMap::mapped_type</h3>
The map's data type.
<h3 class=fn><a name="pointer"></a>QMap::pointer</h3>
Pointer to value_type.
<h3 class=fn><a name="reference"></a>QMap::reference</h3>
Reference to value_type.
<h3 class=fn><a name="size_type"></a>QMap::size_type</h3>
An unsigned integral type, used to represent various sizes.
<h3 class=fn><a name="value_type"></a>QMap::value_type</h3>
Corresponds to <a href="qpair.html">QPair</a><key_type, mapped_type>.
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="QMap"></a>QMap::QMap ()
</h3>
Constructs an empty map.
<h3 class=fn><a name="QMap-2"></a>QMap::QMap ( const <a href="qmap.html">QMap</a><Key, T> & m )
</h3>
Constructs a copy of <em>m</em>.
<p> This operation costs O(1) time because QMap is <a href="shclass.html#implicitly-shared">implicitly shared</a>. The
first instance of applying modifications to a shared map will create a
copy that takes in turn O(n) time. However, returning a QMap from a
function is very fast.
<h3 class=fn><a name="QMap-3"></a>QMap::QMap ( const std::map<Key, T> & m )
</h3>
Constructs a copy of <em>m</em>.
<h3 class=fn><a name="~QMap"></a>QMap::~QMap ()
</h3>
<p> Destroys the map. References to the values in the map and all
iterators of this map become invalidated. Since QMap is highly tuned
for performance you won't see warnings if you use invalid iterators,
because it is not possible for an iterator to check whether it is
valid or not.
<h3 class=fn><a href="qmap.html#iterator">iterator</a> <a name="begin"></a>QMap::begin ()
</h3>
<p> Returns an iterator pointing to the first element in the map. This
iterator equals <a href="#end">end</a>() if the map is empty.
<p> The items in the map are traversed in the order defined by
operator<(Key, Key).
<p> <p>See also <a href="#end">end</a>() and <a href="qmapiterator.html">QMapIterator</a>.
<h3 class=fn><a href="qmap.html#const_iterator">const_iterator</a> <a name="begin-2"></a>QMap::begin () const
</h3>
<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> <p>See also <a href="#end">end</a>() and <a href="qmapconstiterator.html">QMapConstIterator</a>.
<h3 class=fn>void <a name="clear"></a>QMap::clear ()
</h3>
Removes all items from the map.
<p> <p>See also <a href="#remove">remove</a>().
<h3 class=fn>bool <a name="contains"></a>QMap::contains ( const Key & k ) const
</h3>
<p> Returns TRUE if the map contains an item with key <em>k</em>; otherwise
returns FALSE.
<h3 class=fn><a href="qmap.html#size_type">size_type</a> <a name="count"></a>QMap::count ( const <a href="qmap.html#key_type">key_type</a> & k ) const
</h3>
<p> Returns the number of items whose key is <em>k</em>. Since QMap does
not allow duplicate keys, the return value is always 0 or 1.
<p> This function is provided for STL compatibility.
<h3 class=fn><a href="qmap.html#size_type">size_type</a> <a name="count-2"></a>QMap::count () const
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p>
<p> Returns the number of items in the map.
<p> <p>See also <a href="#isEmpty">isEmpty</a>().
<h3 class=fn>void <a name="detach"></a>QMap::detach ()<tt> [protected]</tt>
</h3>
If the map does not share its data with another QMap instance,
nothing happens; otherwise the function creates a new copy of this
map and detaches from the shared one. This function is called
whenever the map is modified. The <a href="shclass.html#implicit-sharing">implicit sharing</a> mechanism is
implemented this way.
<h3 class=fn>bool <a name="empty"></a>QMap::empty () const
</h3>
<p> Returns TRUE if the map contains zero items; otherwise returns FALSE.
<p> This function is provided for STL compatibility. It is equivalent
to <a href="#isEmpty">isEmpty</a>().
<p> <p>See also <a href="#size">size</a>().
<h3 class=fn><a href="qmap.html#iterator">iterator</a> <a name="end"></a>QMap::end ()
</h3>
<p> The iterator returned by <a href="#end">end</a>() points to the element which is one
past the last element in the container. The past-the-end iterator
is still associated with the map it belongs to, however it is <em>not</em> dereferenceable; <a href="qpoint.html#operator*-4">operator*</a>() will not return a well-defined
value.
<p> This iterator equals <a href="#begin">begin</a>() if the map is empty.
<p> <p>See also <a href="#begin">begin</a>() and <a href="qmapiterator.html">QMapIterator</a>.
<h3 class=fn><a href="qmap.html#const_iterator">const_iterator</a> <a name="end-2"></a>QMap::end () const
</h3>
<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> The iterator returned by <a href="#end">end</a>() points to the element which is one
past the last element in the container. The past-the-end iterator
is still associated with the map it belongs to, however it is <em>not</em> dereferenceable; <a href="qpoint.html#operator*-4">operator*</a>() will not return a well-defined
value.
<p> This iterator equals <a href="#begin">begin</a>() if the map is empty.
<p> <p>See also <a href="#begin">begin</a>() and <a href="qmapconstiterator.html">QMapConstIterator</a>.
<h3 class=fn>void <a name="erase"></a>QMap::erase ( <a href="qmap.html#iterator">iterator</a> it )
</h3>
<p> Removes the item associated with the iterator <em>it</em> from the map.
<p> This function is provided for STL compatibility. It is equivalent
to <a href="#remove">remove</a>().
<p> <p>See also <a href="#clear">clear</a>().
<h3 class=fn>void <a name="erase-2"></a>QMap::erase ( const <a href="qmap.html#key_type">key_type</a> & k )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p>
<p> Removes the item with the key <em>k</em> from the map.
<h3 class=fn><a href="qmap.html#iterator">iterator</a> <a name="find"></a>QMap::find ( const Key & k )
</h3>
<p> Returns an iterator pointing to the element with key <em>k</em> in the map.
<p> Returns <a href="#end">end</a>() if no key matched.
<p> <p>See also <a href="qmapiterator.html">QMapIterator</a>.
<h3 class=fn><a href="qmap.html#const_iterator">const_iterator</a> <a name="find-2"></a>QMap::find ( const Key & k ) const
</h3>
<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Returns an iterator pointing to the element with key <em>k</em> in the map.
<p> Returns <a href="#end">end</a>() if no key matched.
<p> <p>See also <a href="qmapconstiterator.html">QMapConstIterator</a>.
<h3 class=fn><a href="qmap.html#iterator">iterator</a> <a name="insert"></a>QMap::insert ( const Key & key, const T & value, bool overwrite = TRUE )
</h3>
<p> Inserts the <em>value</em> with <em>key</em>. If there is already a value
associated with <em>key</em>, it is replaced, unless <em>overwrite</em> is
FALSE (it is TRUE by default).
<h3 class=fn><a href="qpair.html">QPair</a><iterator, bool> <a name="insert-2"></a>QMap::insert ( const <a href="qmap.html#value_type">value_type</a> & x )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p>
<p> Inserts the (key, value) pair <em>x</em> into the map. <em>x</em> is a <a href="qpair.html">QPair</a>
whose <tt>first</tt> element is a key to be inserted and whose <tt>second</tt>
element is the associated value to be inserted. Returns a pair
whose <tt>first</tt> element is an iterator pointing to the inserted item
and whose <tt>second</tt> element is a bool indicating TRUE if <em>x</em> was
inserted and FALSE if it was not inserted because it was already
present.
<h3 class=fn>bool <a name="isEmpty"></a>QMap::isEmpty () const
</h3>
<p> Returns TRUE if the map contains zero items; otherwise returns FALSE.
<p> <p>See also <a href="#count">count</a>().
<h3 class=fn><a href="qmap.html">QMap</a><Key, T> & <a name="operator-eq"></a>QMap::operator= ( const <a href="qmap.html">QMap</a><Key, T> & m )
</h3>
Assigns <em>m</em> to this map and returns a reference to this map.
<p> All iterators of the current map become invalidated by this
operation. The cost of such an assignment is O(1), because QMap is
<a href="shclass.html#implicitly-shared">implicitly shared</a>.
<h3 class=fn><a href="qmap.html">QMap</a><Key, T> & <a name="operator-eq-2"></a>QMap::operator= ( const std::map<Key, T> & m )
</h3>
<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Assigns <em>m</em> to this map and returns a reference to this map.
<p> All iterators of the current map become invalidated by this
operation.
<h3 class=fn>T & <a name="operator[]"></a>QMap::operator[] ( const Key & k )
</h3>
Returns the value associated with the key <em>k</em>. If no such
key is present, an empty item is inserted with this key
and a reference to the item is returned.
<p> You can use this operator both for reading and writing:
<pre>
QMap<QString, QString> map;
map["Clinton"] = "Bill";
stream << map["Clinton"];
</pre>
<h3 class=fn>const T & <a name="operator[]-2"></a>QMap::operator[] ( const Key & k ) const
</h3>
<p> This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> <b>Warning:</b> This function differs from the non-const version of the
same function. It will <em>not</em> insert an empty value if the key <em>k</em>
does not exist. This may lead to logic errors in your program. You
should check if the element exists before calling this function.
<p> Returns the value associated with the key <em>k</em>. If no such
key is present, a reference to an empty item is returned.
<h3 class=fn>void <a name="remove"></a>QMap::remove ( <a href="qmap.html#iterator">iterator</a> it )
</h3>
<p> Removes the item associated with the iterator <em>it</em> from the map.
<p> <p>See also <a href="#clear">clear</a>().
<h3 class=fn>void <a name="remove-2"></a>QMap::remove ( const Key & k )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p>
<p> Removes the item with the key <em>k</em> from the map.
<h3 class=fn><a href="qmap.html#iterator">iterator</a> <a name="replace"></a>QMap::replace ( const Key & k, const T & v )
</h3>
<p> Replaces the value with key <em>k</em> from the map if possible, and
inserts the new value <em>v</em> with key <em>k</em> in the map.
<p> <p>See also <a href="#insert">insert</a>() and <a href="#remove">remove</a>().
<h3 class=fn><a href="qmap.html#size_type">size_type</a> <a name="size"></a>QMap::size () const
</h3>
<p> Returns the number of items in the map.
<p> This function is provided for STL compatibility. It is equivalent
to <a href="#count">count</a>().
<p> <p>See also <a href="#empty">empty</a>().
<hr><h2>Related Functions</h2>
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt"></a>operator<< ( <a href="qdatastream.html">QDataStream</a> & s, const <a href="qmap.html">QMap</a><Key, T> & m )
</h3>
Writes the map <em>m</em> to the stream <em>s</em>. The types <em>Key</em> and <em>T</em>
must implement the streaming operator as well.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt"></a>operator>> ( <a href="qdatastream.html">QDataStream</a> & s, <a href="qmap.html">QMap</a><Key, T> & m )
</h3>
Reads the map <em>m</em> from the stream <em>s</em>. The types <em>Key</em> and <em>T</em>
must implement the streaming operator as well.
<!-- eof -->
<hr><p>
This file is part of the <a href="index.html">Qt toolkit</a>.
Copyright © 1995-2001
<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center>
<table width=100% cellspacing=0 border=0><tr>
<td>Copyright © 2001
<a href="http://www.trolltech.com">Trolltech</a><td><a href="http://www.trolltech.com/trademarks.html">Trademarks</a>
<td align=right><div align=right>Qt version 3.0.2</div>
</table></div></address></body>
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