QMultiHash Class The QMultiHash class is a convenience QHash subclass that provides multi-valued hashes. More...  
 Header:
 #include <QMultiHash> 


 qmake:
 QT += core


 Inherits:
 QHash



 List of all members, including inherited members  Note: All functions in this class are reentrant. Public Functions  
 

QMultiHash()
 
 

QMultiHash(st8b7c:f320:99b9:690f:4595:cd17:293a:c069initializer_list<st8b7c:f320:99b9:690f:4595:cd17:293a:c069pair<Key, T> > list)
 
 

QMultiHash(const QHash<Key, T> &other)
 
 

QMultiHash(QHash<Key, T> &&other)
 
 QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069onst_iterator 

constFind(const Key &key, const T &value) const
 
 bool 

contains(const Key &key, const T &value) const
 
 int 

count(const Key &key, const T &value) const
 
 QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069iterator 

find(const Key &key, const T &value)
 
 QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069onst_iterator 

find(const Key &key, const T &value) const
 
 QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069iterator 

insert(const Key &key, const T &value)
 
 int 

remove(const Key &key, const T &value)
 
 QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069iterator 

replace(const Key &key, const T &value)
 
 void 

swap(QMultiHash &other)
 
 QMultiHash 

operator+(const QMultiHash &other) const
 
 QMultiHash &

operator+=(const QMultiHash &other)
   45 public functions inherited from QHash
  Detailed Description The QMultiHash class is a convenience QHash subclass that provides multi-valued hashes. QMultiHash<Key, T> is one of Qt's generic container classes. It inherits QHash and extends it with a few convenience functions that make it more suitable than QHash for storing multi-valued hashes. A multi-valued hash is a hash that allows multiple values with the same key; QHash normally doesn't allow that, unless you call QHash8b7c:f320:99b9:690f:4595:cd17:293a:c069insertMulti(). Because QMultiHash inherits QHash, all of QHash's functionality also applies to QMultiHash. For example, you can use isEmpty() to test whether the hash is empty, and you can traverse a QMultiHash using QHash's iterator classes (for example, QHashIterator). But in addition, it provides an insert() function that corresponds to QHash8b7c:f320:99b9:690f:4595:cd17:293a:c069insertMulti(), and a replace() function that corresponds to QHash8b7c:f320:99b9:690f:4595:cd17:293a:c069insert(). It also provides convenient operator+() and operator+=(). Example: QMultiHash<QString, int> hash1, hash2, hash3;

hash1.insert("plenty", 100);
hash1.insert("plenty", 2000);
// hash1.size() == 2

hash2.insert("plenty", 5000);
// hash2.size() == 1

hash3 = hash1 + hash2;
// hash3.size() == 3 Unlike QHash, QMultiHash provides no operator[]. Use value() or replace() if you want to access the most recently inserted item with a certain key. If you want to retrieve all the values for a single key, you can use values(const Key &key), which returns a QList<T>: QList<int> values = hash.values("plenty");
for (int i = 0; i < values.size(); ++i)
    cout << values.at(i) << endl; The items that share the same key are available from most recently to least recently inserted. A more efficient approach is to call find() to get the STL-style iterator for the first item with a key and iterate from there: QMultiHash<QString, int>8b7c:f320:99b9:690f:4595:cd17:293a:c069iterator i = hash.find("plenty");
while (i != hash.end() && i.key() == "plenty") {
    cout << i.value() << endl;
    ++i;
} QMultiHash's key and value data types must be assignable data types. You cannot, for example, store a QWidget as a value; instead, store a QWidget *. In addition, QMultiHash's key type must provide operator==(), and there must also be a qHash() function in the type's namespace that returns a hash value for an argument of the key's type. See the QHash documentation for details. See also QHash, QHashIterator, QMutableHashIterator, and QMultiMap. Member Function Documentation 
QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069QMultiHash() Constructs an empty hash. 
QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069QMultiHash(st8b7c:f320:99b9:690f:4595:cd17:293a:c069initializer_list<st8b7c:f320:99b9:690f:4595:cd17:293a:c069pair<Key, T> > list) Constructs a multi hash with a copy of each of the elements in the initializer list list. This function is only available if the program is being compiled in C++11 mode. This function was introduced in Qt 5.1. 
QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069QMultiHash(const QHash<Key, T> &other) Constructs a copy of other (which can be a QHash or a QMultiHash). See also operator=(). 
QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069QMultiHash(QHash<Key, T> &&other) Default constructs an instance of QMultiHash. 
QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069onst_iterator QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069onstFind(const Key &key, const T &value) const Returns an iterator pointing to the item with the key and the value in the hash. If the hash contains no such item, the function returns constEnd(). This function was introduced in Qt 4.3. See also QHash8b7c:f320:99b9:690f:4595:cd17:293a:c069onstFind(). 
bool QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069ontains(const Key &key, const T &value) const Returns true if the hash contains an item with the key and value; otherwise returns false. This function was introduced in Qt 4.3. See also QHash8b7c:f320:99b9:690f:4595:cd17:293a:c069ontains(). 
int QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069ount(const Key &key, const T &value) const Returns the number of items with the key and value. This function was introduced in Qt 4.3. See also QHash8b7c:f320:99b9:690f:4595:cd17:293a:c069ount(). 
QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069iterator QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069ind(const Key &key, const T &value) Returns an iterator pointing to the item with the key and value. If the hash contains no such item, the function returns end(). If the hash contains multiple items with the key and value, the iterator returned points to the most recently inserted item. This function was introduced in Qt 4.3. See also QHash8b7c:f320:99b9:690f:4595:cd17:293a:c069ind(). 
QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069onst_iterator QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069ind(const Key &key, const T &value) const This is an overloaded function. This function was introduced in Qt 4.3. 
QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069iterator QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069insert(const Key &key, const T &value) Inserts a new item with the key and a value of value. If there is already an item with the same key in the hash, this function will simply create a new one. (This behavior is different from replace(), which overwrites the value of an existing item.) See also replace(). 
int QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069remove(const Key &key, const T &value) Removes all the items that have the key and the value value from the hash. Returns the number of items removed. This function was introduced in Qt 4.3. See also QHash8b7c:f320:99b9:690f:4595:cd17:293a:c069remove(). 
QHash<Key, T>8b7c:f320:99b9:690f:4595:cd17:293a:c069iterator QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069replace(const Key &key, const T &value) Inserts a new item with the key and a value of value. If there is already an item with the key, that item's value is replaced with value. If there are multiple items with the key, the most recently inserted item's value is replaced with value. See also insert(). 
void QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069swap(QMultiHash &other) Swaps hash other with this hash. This operation is very fast and never fails. This function was introduced in Qt 4.8. 
QMultiHash QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069operator+(const QMultiHash &other) const Returns a hash that contains all the items in this hash in addition to all the items in other. If a key is common to both hashes, the resulting hash will contain the key multiple times. See also operator+=(). 
QMultiHash &QMultiHash8b7c:f320:99b9:690f:4595:cd17:293a:c069operator+=(const QMultiHash &other) Inserts all the items in the other hash into this hash and returns a reference to this hash. See also insert().

    
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