ConstIterator 类

class QCborArray ::ConstIterator

The QCborArray::ConstIterator 类提供 STL 样式 const 迭代器为 QCborArray . 更多...

公共类型

iterator_category

公共函数

ConstIterator ()
ConstIterator (const ConstIterator & other )
bool operator!= (const Iterator & o ) const
bool operator!= (const ConstIterator & o ) const
QCborValueConstRef operator* () const
ConstIterator operator+ (qsizetype j ) const
ConstIterator & operator++ ()
ConstIterator operator++ (int)
ConstIterator & operator+= (qsizetype j )
ConstIterator operator- (qsizetype j ) const
qsizetype operator- (ConstIterator other ) const
ConstIterator & operator-- ()
ConstIterator operator-- (int)
ConstIterator & operator-= (qsizetype j )
const QCborValueConstRef * 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
ConstIterator & operator= (const ConstIterator & other )
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
QCborValueConstRef operator[] (qsizetype j ) const

详细描述

QCborArray::ConstIterator allows you to iterate over a QCborArray . If you want to modify the QCborArray as you iterate over it, use QCborArray::Iterator instead. It is generally good practice to use QCborArray::ConstIterator , even on a non-const QCborArray , when you don't need to change the QCborArray through the iterator. Const iterators are slightly faster and improves code readability.

Iterators are initialized by using a QCborArray function like QCborArray::begin () 或 QCborArray::end (). Iteration is only possible after that.

Most QCborArray functions accept an integer index rather than an iterator. For that reason, iterators are rarely useful in connection with QCborArray . One place where STL-style iterators do make sense is as arguments to 一般算法 .

Multiple iterators can be used on the same array. However, be aware that any non-const function call performed on the QCborArray will render all existing iterators undefined.

另请参阅 QCborArray::Iterator .

成员类型文档编制

ConstIterator:: iterator_category

同义词 std::random_access_iterator_tag indicating this iterator is a random access iterator.

成员函数文档编制

bool ConstIterator:: operator== (const ConstIterator & other ) const

bool ConstIterator:: operator== (const Iterator & other ) const

返回 true if other points to the same entry in the array as this iterator; otherwise returns false .

另请参阅 operator!= ().

bool ConstIterator:: operator!= (const ConstIterator & o ) const

bool ConstIterator:: operator!= (const Iterator & o ) const

返回 true if o points to a different entry in the array than this iterator; otherwise returns false .

另请参阅 operator== ().

bool ConstIterator:: operator< (const ConstIterator & other ) const

bool ConstIterator:: operator< (const Iterator & other ) const

返回 true if the entry in the array pointed to by this iterator occurs before the entry pointed to by the other iterator.

bool ConstIterator:: operator<= (const ConstIterator & other ) const

bool ConstIterator:: operator<= (const Iterator & other ) const

返回 true if the entry in the array pointed to by this iterator occurs before or is the same entry as is pointed to by the other iterator.

bool ConstIterator:: operator> (const ConstIterator & other ) const

bool ConstIterator:: operator> (const Iterator & other ) const

返回 true if the entry in the array pointed to by this iterator occurs after the entry pointed to by the other iterator.

bool ConstIterator:: operator>= (const ConstIterator & other ) const

bool ConstIterator:: operator>= (const Iterator & other ) const

返回 true if the entry in the array pointed to by this iterator occurs after or is the same entry as is pointed to by the other iterator.

[constexpr] ConstIterator:: ConstIterator ()

Constructs an uninitialized iterator.

Functions like operator*() and operator++() should not be called on an uninitialized iterator. Use operator=() to assign a value to it before using it.

另请参阅 QCborArray::constBegin () 和 QCborArray::constEnd ().

[constexpr] ConstIterator:: ConstIterator (const ConstIterator & other )

构造副本为 other .

QCborValueConstRef ConstIterator:: operator* () const

返回当前项。

ConstIterator ConstIterator:: operator+ ( qsizetype j ) const

Returns an iterator to the item at a position j steps forward from this iterator. If j is negative, the iterator goes backward.

另请参阅 operator- () 和 operator+= ().

ConstIterator &ConstIterator:: operator++ ()

The prefix ++ operator, ++it , advances the iterator to the next item in the array and returns this iterator.

Calling this function on QCborArray::end () leads to undefined results.

另请参阅 operator-- ().

ConstIterator ConstIterator:: operator++ ( int )

这是重载函数。

The postfix ++ operator, it++ , advances the iterator to the next item in the array and returns an iterator to the previously current item.

ConstIterator &ConstIterator:: operator+= ( qsizetype j )

Advances the iterator by j positions. If j is negative, the iterator goes backward. Returns a reference to this iterator.

另请参阅 operator-= () 和 operator+ ().

ConstIterator ConstIterator:: operator- ( qsizetype j ) const

Returns an iterator to the item at a position j steps backward from this iterator. If j is negative, the iterator goes forward.

另请参阅 operator+ () 和 operator-= ().

qsizetype ConstIterator:: operator- ( ConstIterator other ) const

Returns the offset of this iterator relative to other .

ConstIterator &ConstIterator:: operator-- ()

The prefix -- operator, --it , makes the preceding item current and returns this iterator.

Calling this function on QCborArray::begin () leads to undefined results.

另请参阅 operator++ ().

ConstIterator ConstIterator:: operator-- ( int )

这是重载函数。

The postfix -- operator, it-- , makes the preceding item current and returns an iterator to the previously current item.

ConstIterator &ConstIterator:: operator-= ( qsizetype j )

Makes the iterator go back by j positions. If j is negative, the iterator goes forward. Returns a reference to this iterator.

另请参阅 operator+= () 和 operator- ().

const QCborValueConstRef *ConstIterator:: operator-> () const

Returns a pointer to the current item.

ConstIterator &ConstIterator:: operator= (const ConstIterator & other )

Makes this iterator a copy of other and returns a reference to this iterator.

QCborValueConstRef ConstIterator:: operator[] ( qsizetype j ) const

Returns the item at a position j steps forward from the item pointed to by this iterator.

This function is provided to make QCborArray iterators behave like C++ pointers.

另请参阅 operator+ ().