iterator Class | Qt Core 5.15.19 (original) (raw)

This class was introduced in Qt 5.0.

Member Function Documentation

bool iterator::operator>=(const const_iterator &other) const

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

Returns true if the item pointed to by this iterator is greater than or equal to the item pointed to by the other iterator.

bool iterator::operator>(const const_iterator &other) const

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

Returns true if the item pointed to by this iterator is greater than the item pointed to by the other iterator.

bool iterator::operator<=(const const_iterator &other) const

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

Returns true if the item pointed to by this iterator is less than or equal to the item pointed to by the other iterator.

bool iterator::operator<(const const_iterator &other) const

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

Returns true if the item pointed to by this iterator is less than the item pointed to by the other iterator.

bool iterator::operator!=(const const_iterator &other) const

bool iterator::operator!=(const iterator &other) const

Returns true if other points to a different item than this iterator; otherwise returns false.

See also operator==().

bool iterator::operator==(const const_iterator &other) const

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

Returns true if other points to the same item as this iterator; otherwise returns false.

See also operator!=().

iterator::iterator()

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.

See also QJsonObject::begin() and QJsonObject::end().

QString iterator::key() const

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 QJsonObject::erase() followed by QJsonObject::insert().

See also value().

QJsonValueRef iterator::value() const

Returns a modifiable reference to the current item's value.

You can change the value of an item by using value() on the left side of an assignment.

The return value is of type QJsonValueRef, a helper class for QJsonArray and QJsonObject. When you get an object of type QJsonValueRef, you can use it as if it were a reference to a QJsonValue. If you assign to it, the assignment will apply to the element in the QJsonArray or QJsonObject from which you got the reference.

See also key() and operator*().

QJsonValueRef iterator::operator*() const

Returns a modifiable reference to the current item's value.

Same as value().

The return value is of type QJsonValueRef, a helper class for QJsonArray and QJsonObject. When you get an object of type QJsonValueRef, you can use it as if it were a reference to a QJsonValue. If you assign to it, the assignment will apply to the element in the QJsonArray or QJsonObject from which you got the reference.

See also key().

iterator iterator::operator+(int j) const

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

See also operator-().

iterator &iterator::operator++()

The prefix ++ operator, ++i, advances the iterator to the next item in the object and returns an iterator to the new current item.

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

See also operator--().

iterator iterator::operator++(int)

This is an overloaded function.

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

iterator &iterator::operator+=(int j)

Advances the iterator by j items. If j is negative, the iterator goes backward.

See also operator-=() and operator+().

iterator iterator::operator-(int j) const

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

See also operator+().

int iterator::operator-(iterator other) const

Returns the number of items between the item pointed to by other and the item pointed to by this iterator.

iterator &iterator::operator--()

The prefix -- operator, --i, makes the preceding item current and returns an iterator pointing to the new current item.

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

See also operator++().

iterator iterator::operator--(int)

This is an overloaded function.

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

iterator &iterator::operator-=(int j)

Makes the iterator go back by j items. If j is negative, the iterator goes forward.

See also operator+=() and operator-().

QJsonValueRef *iterator::operator->() const

Returns a pointer to a modifiable reference to the current item.

const QJsonValueRef iterator::operator[](int _j_)

Returns a modifiable reference to the item at offset j from the item pointed to by this iterator (the item at position *this + j).

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

The return value is of type QJsonValueRef, a helper class for QJsonArray and QJsonObject. When you get an object of type QJsonValueRef, you can use it as if it were a reference to a QJsonValue. If you assign to it, the assignment will apply to the element in the QJsonArray or QJsonObject from which you got the reference.

See also operator+().