QJSValueIterator Class

The QJSValueIterator class provides a Java-style iterator for QJSValue. 更多...

头文件:	#include <QJSValueIterator>
qmake:	QT += qml

所有的成员列表, 包括继承的成员

公有函数

	QJSValueIterator(const QJSValue &object)
	~QJSValueIterator()
bool	hasNext() const
QString	name() const
bool	next()
QJSValue	value() const
QJSValueIterator &	operator=(QJSValue &object)

详细描述

The QJSValueIterator class provides a Java-style iterator for QJSValue.

The QJSValueIterator constructor takes a QJSValue as argument. After construction, the iterator is located at the very beginning of the sequence of properties. Here's how to iterate over all the properties of a QJSValue:


  QJSValue object;
  ...
  QJSValueIterator it(object);
  while (it.hasNext()) {
      it.next();
      qDebug() << it.name() << ": " << it.value().toString();
  }

The next() advances the iterator. The name() and value() functions return the name and value of the last item that was jumped over.

Note that QJSValueIterator only iterates over the QJSValue's own properties; i.e. it does not follow the prototype chain. You can use a loop like this to follow the prototype chain:


  QJSValue obj = ...; // the object to iterate over
  while (obj.isObject()) {
      QJSValueIterator it(obj);
      while (it.hasNext()) {
          it.next();
          qDebug() << it.name();
      }
      obj = obj.prototype();
  }

参见 QJSValue::property().

成员函数

QJSValueIterator::QJSValueIterator(const QJSValue &object)

Constructs an iterator for traversing object. The iterator is set to be at the front of the sequence of properties (before the first property).

QJSValueIterator::~QJSValueIterator()

Destroys the iterator.

bool QJSValueIterator::hasNext() const

Returns true if there is at least one item ahead of the iterator (i.e. the iterator is not at the back of the property sequence); otherwise returns false.

参见 next().

QString QJSValueIterator::name() const

Returns the name of the last property that was jumped over using next().

参见 value().

bool QJSValueIterator::next()

Advances the iterator by one position. Returns true if there was at least one item ahead of the iterator (i.e. the iterator was not already at the back of the property sequence); otherwise returns false.

参见 hasNext() and name().

QJSValue QJSValueIterator::value() const

Returns the value of the last property that was jumped over using next().

参见 name().

QJSValueIterator &QJSValueIterator::operator=(QJSValue &object)

Makes the iterator operate on object. The iterator is set to be at the front of the sequence of properties (before the first property).

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