内容

• 公共函数
• 相关非成员
• 详细描述

QKeyValueIterator 类

template <typename Key, typename T, typename Iterator> class QKeyValueIterator

迭代关联容器的键/值对。 更多...

头：	#include <QKeyValueIterator>
qmake:	QT += core
Since:	Qt 5.10

该类在 Qt 5.10 引入。

• 所有成员列表，包括继承成员

公共函数

	QKeyValueIterator (Iterator o )
	QKeyValueIterator ()
Iterator	base () const
std::pair<Key, T>	operator* () const
QKeyValueIterator<Key, T, Iterator> &	operator++ ()
QKeyValueIterator<Key, T, Iterator>	operator++ ( int )
QKeyValueIterator<Key, T, Iterator> &	operator-- ()
QKeyValueIterator<Key, T, Iterator>	operator-- ( int )
QKeyValueIterator::pointer	operator-> () const

相关非成员

bool	operator!= (QKeyValueIterator<Key, T, Iterator> lhs , QKeyValueIterator<Key, T, Iterator> rhs )
bool	operator== (QKeyValueIterator<Key, T, Iterator> lhs , QKeyValueIterator<Key, T, Iterator> rhs )

详细描述

The QKeyValueIterator class provides an STL-style iterator for returning key/value pairs from associative containers like QHash and QMap . It supports the same API as the STL associative containers, i.e. getting a key/value pair when iterating through the container.

This will allow for better interoperability between QMap , QHash and friends and STL-style algorithms.

警告： Iterators on implicitly shared containers do not work exactly like STL-iterators. You should avoid copying a container while iterators are active on that container. For more information, read 隐式共享迭代器问题 .

成员函数文档编制

QKeyValueIterator:: QKeyValueIterator ( Iterator o )

Constructs a QKeyValueIterator on top of o .

QKeyValueIterator:: QKeyValueIterator ()

构造默认 QKeyValueIterator。

Iterator QKeyValueIterator:: base () const

Returns the underlying iterator this QKeyValueIterator is based on.

std::pair < Key , T > QKeyValueIterator:: operator* () const

成对返回当前条目。

QKeyValueIterator < Key , T , Iterator > &QKeyValueIterator:: operator++ ()

The prefix ++ operator ( ++i ) advances the iterator to the next item in the container and returns the iterator.

注意： Advancing the iterator past its container's end() constitutes undefined behavior.

另请参阅 operator-- ().

QKeyValueIterator < Key , T , Iterator > QKeyValueIterator:: operator++ ( int )

这是重载函数。

The postfix ++ operator ( i++ ) advances the iterator to the next item in the container and returns the iterator's prior value.

注意： Advancing the iterator past its container's end() constitutes undefined behavior.

QKeyValueIterator < Key , T , Iterator > &QKeyValueIterator:: operator-- ()

The prefix -- operator ( --i ) backs the iterator up to the previous item in the container and returns the iterator.

注意： Backing up an iterator to before its container's begin() constitutes undefined behavior.

另请参阅 operator++ ().

QKeyValueIterator < Key , T , Iterator > QKeyValueIterator:: operator-- ( int )

这是重载函数。

The postfix -- operator ( i-- ) backs the iterator up to the previous item in the container and returns the iterator's prior value.

注意： Backing up an iterator to before its container's begin() constitutes undefined behavior.

QKeyValueIterator::pointer QKeyValueIterator:: operator-> () const

Returns the current entry as a pointer-like object to the pair.

该函数在 Qt 5.15 引入。

另请参阅 operator* ().

相关非成员

bool operator!= ( QKeyValueIterator < Key , T , Iterator > lhs , QKeyValueIterator < Key , T , Iterator > rhs )

返回 true if rhs points to a different item than lhs otherwise returns false .

另请参阅 operator== ().

bool operator== ( QKeyValueIterator < Key , T , Iterator > lhs , QKeyValueIterator < Key , T , Iterator > rhs )

返回 true if rhs points to the same item as lhs otherwise returns false .

另请参阅 operator!= ().