The QCborMap::Iterator 类提供 STL 样式非常量迭代器为 QCborMap . 更多...
该类在 Qt 5.12 引入。
typedef | iterator_category |
Iterator (const Iterator & other ) | |
Iterator () | |
Iterator & | operator= (const Iterator & other ) |
QCborValue | key () const |
QCborValueRef | value () const |
bool | operator!= (const Iterator & other ) const |
bool | operator!= (const ConstIterator & other ) const |
Iterator::value_type | operator* () const |
迭代器 | operator+ (qsizetype j ) const |
Iterator & | operator++ () |
迭代器 | operator++ ( int ) |
Iterator & | operator+= (qsizetype j ) |
迭代器 | operator- (qsizetype j ) const |
qsizetype | operator- (Iterator j ) const |
Iterator & | operator-- () |
迭代器 | operator-- ( int ) |
Iterator & | operator-= (qsizetype j ) |
QCborValueRef * | operator-> () const |
bool | operator< (const Iterator & other ) const |
bool | operator< (const ConstIterator & other ) const |
bool | operator<= (const Iterator & other ) const |
bool | operator<= (const ConstIterator & other ) const |
bool | operator== (const Iterator & other ) const |
bool | operator== (const ConstIterator & other ) const |
bool | operator> (const Iterator & other ) const |
bool | operator> (const ConstIterator & other ) const |
bool | operator>= (const Iterator & other ) const |
bool | operator>= (const ConstIterator & other ) const |
QCborMap::Iterator allows you to iterate over a QCborMap and to modify the value (but not the key) stored under a particular key. If you want to iterate over a const QCborMap , you should use QCborMap::ConstIterator . It is generally good practice to use QCborMap::ConstIterator on a non-const QCborMap as well, unless you need to change the QCborMap through the iterator. Const iterators are slightly faster, and improve code readability.
You must initialize the iterator using a QCborMap function like QCborMap::begin (), QCborMap::end (),或 QCborMap::find () before you can start iterating..
Multiple iterators can be used on the same object. Existing iterators will however become dangling once the object gets modified.
另请参阅 QCborMap::ConstIterator .
同义词 std::random_access_iterator_tag indicating this iterator is a random-access iterator.
返回
true
if the entry in the map pointed to by this iterator occurs after or is the same entry as is pointed to by the
other
iterator.
返回
true
if the entry in the map pointed to by this iterator occurs after the entry pointed to by the
other
iterator.
返回
true
if the entry in the map pointed to by this iterator occurs before or is the same entry as is pointed to by the
other
iterator.
返回
true
if the entry in the map pointed to by this iterator occurs before the entry pointed to by the
other
iterator.
返回
true
if
other
points to a different entry in the map than this iterator; otherwise returns
false
.
另请参阅 operator== ().
返回
true
if
other
points to the same entry in the map as this iterator; otherwise returns
false
.
另请参阅 operator!= ().
Constructs an iterator as a copy of other .
Constructs an uninitialized iterator.
Functions like key (), value (), and operator++() must not be called on an uninitialized iterator. Use operator=() to assign a value to it before using it.
另请参阅 QCborMap::begin () 和 QCborMap::end ().
Makes this iterator a copy of other and returns a reference to this iterator.
Returns the current item's key.
There is no direct way of changing an item's key through an iterator, although it can be done by calling QCborMap::erase () followed by QCborMap::insert ().
另请参阅 value ().
Returns a modifiable reference to the current item's value.
You can change the value for a key by using value() on the left side of an assignment.
The return value is of type QCborValueRef , a helper class for QCborArray and QCborMap . When you get an object of type QCborValueRef , you can use it as if it were a reference to a QCborValue . If you assign to it, the assignment will apply to the element in the QCborArray or QCborMap from which you got the reference.
Returns a pair containing the current item's key and a modifiable reference to the current item's value.
The second element of the pair is of type QCborValueRef , a helper class for QCborArray and QCborMap . When you get an object of type QCborValueRef , you can use it as if it were a reference to a QCborValue . If you assign to it, the assignment will apply to the element in the QCborArray or QCborMap from which you got the reference.
Returns an iterator to the item at j positions forward from this iterator. If j is negative, the iterator goes backward.
另请参阅 operator- ().
The prefix ++ operator,
++i
, advances the iterator to the next item in the map and returns this iterator.
Calling this function on QCborMap::end () leads to undefined results.
另请参阅 operator-- ().
这是重载函数。
The postfix ++ operator,
i++
, advances the iterator to the next item in the map and returns an iterator to the previously current item.
Advances the iterator by j items. If j is negative, the iterator goes backward. Returns a reference to this iterator.
另请参阅 operator-= () 和 operator+ ().
Returns an iterator to the item at j positions backward from this iterator. If j is negative, the iterator goes forward.
另请参阅 operator+ ().
Returns the position of the item at iterator j relative to the item at this iterator. If the item at j is forward of this time, the returned value is negative.
另请参阅 operator+ ().
The prefix -- operator,
--i
, makes the preceding item current and returns this iterator.
Calling this function on QCborMap::begin () leads to undefined results.
另请参阅 operator++ ().
这是重载函数。
The postfix -- operator,
i--
, makes the preceding item current and returns an iterator pointing to the previously current item.
Makes the iterator go back by j items. If j is negative, the iterator goes forward. Returns a reference to this iterator.
另请参阅 operator+= () 和 operator- ().
Returns a pointer to a modifiable reference to the current pair's value.