QScriptValueIterator Class Reference

The QScriptValueIterator class provides a Java-style iterator for QScriptValue. More...

 #include <QScriptValueIterator>

This class was introduced in Qt 4.3.

List of all members, including inherited members

Public Functions

	QScriptValueIterator ( const QScriptValue & object )
	~QScriptValueIterator ()
QScriptValue::PropertyFlags	flags () const
bool	hasNext () const
bool	hasPrevious () const
QString	name () const
void	next ()
void	previous ()
void	remove ()
QScriptString	scriptName () const
void	setValue ( const QScriptValue & value )
void	toBack ()
void	toFront ()
QScriptValue	value () const
QScriptValueIterator &	operator= ( QScriptValue & object )

Detailed Description

The QScriptValueIterator class provides a Java-style iterator for QScriptValue.

The QScriptValueIterator constructor takes a QScriptValue 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 QScriptValue:

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

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

If you want to remove properties as you iterate over the QScriptValue, use remove(). If you want to modify the value of a property, use setValue().

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

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

Note that QScriptValueIterator will not automatically skip over properties that have the QScriptValue::SkipInEnumeration flag set; that flag only affects iteration in script code. If you want, you can skip over such properties with code like the following:

 while (it.hasNext()) {
     it.next();
     if (it.flags() & QScriptValue::SkipInEnumeration)
         continue;
     qDebug() << "found enumerated property:" << it.name();
 }

Member Function Documentation

QScriptValueIterator::QScriptValueIterator ( const QScriptValue & 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).

QScriptValueIterator::~QScriptValueIterator ()

Destroys the iterator.

QScriptValue::PropertyFlags QScriptValueIterator::flags () const

Returns the flags of the last property that was jumped over using next() or previous().

bool QScriptValueIterator::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.

bool QScriptValueIterator::hasPrevious () const

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

QString QScriptValueIterator::name () const

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

void QScriptValueIterator::next ()

Advances the iterator by one position.

Calling this function on an iterator located at the back of the container leads to undefined results.

See also hasNext(), previous(), and name().

void QScriptValueIterator::previous ()

Moves the iterator back by one position.

Calling this function on an iterator located at the front of the container leads to undefined results.

See also hasPrevious(), next(), and name().

void QScriptValueIterator::remove ()

Removes the last property that was jumped over using next() or previous().

QScriptString QScriptValueIterator::scriptName () const

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

This function was introduced in Qt 4.4.

void QScriptValueIterator::setValue ( const QScriptValue & value )

Sets the value of the last property that was jumped over using next() or previous().

void QScriptValueIterator::toBack ()

Moves the iterator to the back of the QScriptValue (after the last property).

void QScriptValueIterator::toFront ()

Moves the iterator to the front of the QScriptValue (before the first property).

QScriptValue QScriptValueIterator::value () const

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

QScriptValueIterator & QScriptValueIterator::operator= ( QScriptValue & 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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