内容

• 公共函数
• 公共槽
• 保护函数
• 详细描述

QAbstractNetworkCache 类

QAbstractNetworkCache class provides the interface for cache implementations. 更多...

头：	#include <QAbstractNetworkCache>
qmake:	QT += network
Since:	Qt 4.5
继承：	QObject
继承者：	QNetworkDiskCache

• 所有成员列表，包括继承成员

公共函数

virtual	~QAbstractNetworkCache ()
virtual qint64	cacheSize () const = 0
virtual QIODevice *	data (const QUrl & url ) = 0
virtual void	insert (QIODevice * device ) = 0
virtual QNetworkCacheMetaData	metaData (const QUrl & url ) = 0
virtual QIODevice *	prepare (const QNetworkCacheMetaData & metaData ) = 0
virtual bool	remove (const QUrl & url ) = 0
virtual void	updateMetaData (const QNetworkCacheMetaData & metaData ) = 0

• 32 公共函数继承自 QObject

公共槽

virtual void

clear () = 0

• 1 公共槽继承自 QObject

保护函数

QAbstractNetworkCache (QObject * parent = Q_NULLPTR)

• 9 保护函数继承自 QObject

额外继承成员

• 1 特性继承自 QObject
• 2 信号继承自 QObject
• 11 静态公共成员继承自 QObject

详细描述

QAbstractNetworkCache class provides the interface for cache implementations.

QAbstractNetworkCache is the base class for every standard cache that is used by QNetworkAccessManager . QAbstractNetworkCache is an abstract class and cannot be instantiated.

另请参阅 QNetworkDiskCache .

成员函数文档编制

[protected] QAbstractNetworkCache:: QAbstractNetworkCache ( QObject * parent = Q_NULLPTR)

构造抽象网络缓存采用给定 parent .

[virtual] QAbstractNetworkCache:: ~QAbstractNetworkCache ()

销毁缓存。

Any operations that have not been inserted are discarded.

另请参阅 insert ().

[pure virtual] qint64 QAbstractNetworkCache:: cacheSize () const

Returns the current size taken up by the cache. Depending upon the cache implementation this might be disk or memory size.

在基类中，这是纯虚函数。

另请参阅 clear ().

[pure virtual slot] void QAbstractNetworkCache:: clear ()

Removes all items from the cache. Unless there was failures clearing the cache cacheSize () should return 0 after a call to clear.

在基类中，这是纯虚函数。

另请参阅 cacheSize () 和 remove ().

[pure virtual] QIODevice *QAbstractNetworkCache:: data (const QUrl & url )

Returns the data associated with url .

It is up to the application that requests the data to delete the QIODevice when done with it.

If there is no cache for url , the url is invalid, or if there is an internal cache error 0 is returned.

在基类中，这是纯虚函数。

另请参阅 metaData () 和 prepare ().

[pure virtual] void QAbstractNetworkCache:: insert ( QIODevice * device )

Inserts the data in device and the prepared meta data into the cache. After this function is called the data and meta data should be retrievable using data () 和 metaData ().

To cancel a prepared inserted call remove () on the metadata's url.

在基类中，这是纯虚函数。

另请参阅 prepare () 和 remove ().

[pure virtual] QNetworkCacheMetaData QAbstractNetworkCache:: metaData (const QUrl & url )

Returns the meta data for the url url .

If the url is valid and the cache contains the data for url, a valid QNetworkCacheMetaData 被返回。

在基类中，这是纯虚函数。

另请参阅 updateMetaData () 和 data ().

[pure virtual] QIODevice *QAbstractNetworkCache:: prepare (const QNetworkCacheMetaData & metaData )

Returns the device that should be populated with the data for the cache item metaData . When all of the data has been written insert () should be called. If metaData is invalid or the url in the metadata is invalid 0 is returned.

The cache owns the device and will take care of deleting it when it is inserted or removed.

To cancel a prepared inserted call remove () on the metadata's url.

在基类中，这是纯虚函数。

另请参阅 remove (), updateMetaData ()，和 insert ().

[pure virtual] bool QAbstractNetworkCache:: remove (const QUrl & url )

Removes the cache entry for url , returning true if success otherwise false.

在基类中，这是纯虚函数。

另请参阅 clear () 和 prepare ().

[pure virtual] void QAbstractNetworkCache:: updateMetaData (const QNetworkCacheMetaData & metaData )

Updates the cache meta date for the metaData 's url to metaData

If the cache does not contains a cache item for the url then no action is taken.

在基类中，这是纯虚函数。

另请参阅 metaData () 和 prepare ().