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QPdfDocument 类

QPdfDocument 类加载 PDF 文档并渲染其页面。 更多...

头： #include <QPdfDocument>
继承： QObject

公共类型

enum class Error { None, Unknown, DataNotYetAvailable, FileNotFound, InvalidFileFormat, …, UnsupportedSecurityScheme }
enum class MetaDataField { Title, Author, Subject, Keywords, Creator, …, ModificationDate }
enum class PageModelRole { Label, PointSize }
enum class Status { Null, Loading, Ready, Unloading, Error }

特性

公共函数

QPdfDocument (QObject * parent )
virtual ~QPdfDocument () override
void close ()
QPdfDocument::Error error () const
QPdfSelection getAllText (int page )
QPdfSelection getSelection (int page , QPointF start , QPointF end )
QPdfSelection getSelectionAtIndex (int page , int startIndex , int maxLength )
QPdfDocument::Error load (const QString & fileName )
void load (QIODevice * device )
QVariant metaData (QPdfDocument::MetaDataField field ) const
int pageCount () const
QString pageLabel (int page )
QAbstractListModel * pageModel ()
QSizeF pagePointSize (int page ) const
QString password () const
QImage render (int page , QSize imageSize , QPdfDocumentRenderOptions renderOptions = QPdfDocumentRenderOptions())
void setPassword (const QString & password )
QPdfDocument::Status status () const

信号

void pageCountChanged (int pageCount )
void pageModelChanged ()
void passwordChanged ()
void statusChanged (QPdfDocument::Status status )

详细描述

成员类型文档编制

enum class QPdfDocument:: Error

This enum describes the error while attempting the last operation on the document.

常量 值 描述
QPdfDocument::Error::None 0 没有出现错误。
QPdfDocument::Error::Unknown 1 Unknown type of error.
QPdfDocument::Error::DataNotYetAvailable 2 The document is still loading, it's too early to attempt the operation.
QPdfDocument::Error::FileNotFound 3 The file given to load () was not found.
QPdfDocument::Error::InvalidFileFormat 4 The file given to load () is not a valid PDF file.
QPdfDocument::Error::IncorrectPassword 5 The password given to setPassword () is not correct for this file.
QPdfDocument::Error::UnsupportedSecurityScheme 6 QPdfDocument is not able to unlock this kind of PDF file.

另请参阅 QPdfDocument::error ().

enum class QPdfDocument:: MetaDataField

此枚举描述元数据的可用字段。

常量 值 描述
QPdfDocument::MetaDataField::Title 0 文档的标题作为 QString .
QPdfDocument::MetaDataField::Author 2 The name of the person who created the document as QString .
QPdfDocument::MetaDataField::Subject 1 The subject of the document as QString .
QPdfDocument::MetaDataField::Keywords 3 Keywords associated with the document as QString .
QPdfDocument::MetaDataField::Creator 5 If the document was converted to PDF from another format, the name of the conforming product that created the original document from which it was converted as QString .
QPdfDocument::MetaDataField::Producer 4 If the document was converted to PDF from another format, the name of the conforming product that converted it to PDF as QString .
QPdfDocument::MetaDataField::CreationDate 6 The date and time the document was created as QDateTime .
QPdfDocument::MetaDataField::ModificationDate 7 The date and time the document was most recently modified as QDateTime .

另请参阅 QPdfDocument::metaData ().

enum class QPdfDocument:: PageModelRole

Roles in pageModel ().

常量 值 描述
QPdfDocument::PageModelRole::Label Qt::UserRole The page number to be used for display purposes ( QString ).
QPdfDocument::PageModelRole::PointSize 257 The page size in points (1/72 of an inch) ( QSizeF ).

enum class QPdfDocument:: Status

此枚举描述文档的当前状态。

常量 值 描述
QPdfDocument::Status::Null 0 The initial status after the document has been created or after it has been closed.
QPdfDocument::Status::Loading 1 The status after load () has been called and before the document is fully loaded.
QPdfDocument::Status::Ready 2 The status when the document is fully loaded and its data can be accessed.
QPdfDocument::Status::Unloading 3 The status after close () has been called on an open document. At this point the document is still valid and all its data can be accessed.
QPdfDocument::Status::Error 4 加载后的状态，若加载失败。

另请参阅 QPdfDocument::status ().

特性文档编制

[read-only] pageCount : const int

This property holds the number of pages in the loaded document or 0 if no document is loaded.

访问函数：

int pageCount () const

通知程序信号：

void pageCountChanged (int pageCount )

[read-only] pageModel : QAbstractListModel * const

This property holds an instance of QAbstractListModel to provide page-specific metadata, containing one row for each page in the document.

访问函数：

QAbstractListModel * pageModel ()

通知程序信号：

void pageModelChanged ()

另请参阅 QPdfDocument::PageModelRole .

password : QString

This property holds the document password.

If the document is protected by a password, the user must provide it, and the application must set this property. Otherwise, it's not needed.

访问函数：

QString password () const
void setPassword (const QString & password )

通知程序信号：

void passwordChanged ()

[read-only] status : const Status

This property holds the current status of the document.

访问函数：

QPdfDocument::Status status () const

通知程序信号：

void statusChanged (QPdfDocument::Status status )

成员函数文档编制

[explicit] QPdfDocument:: QPdfDocument ( QObject * parent )

构造新文档采用父级对象 parent .

[override virtual] QPdfDocument:: ~QPdfDocument ()

销毁文档。

void QPdfDocument:: close ()

关闭文档。

QPdfDocument::Error QPdfDocument:: error () const

Returns the type of error if status is Error ，或 NoError if there is no error.

[invokable] QPdfSelection QPdfDocument:: getAllText ( int page )

返回所有文本及其边界在给定 page .

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

[invokable] QPdfSelection QPdfDocument:: getSelection ( int page , QPointF start , QPointF end )

Returns information about the text on the given page that can be found between the given start and end points, if any.

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

[invokable] QPdfSelection QPdfDocument:: getSelectionAtIndex ( int page , int startIndex , int maxLength )

Returns information about the text on the given page that can be found beginning at the given startIndex with at most maxLength 字符。

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

QPdfDocument::Error QPdfDocument:: load (const QString & fileName )

Loads the document contents from fileName .

void QPdfDocument:: load ( QIODevice * device )

Loads the document contents from device .

QVariant QPdfDocument:: metaData ( QPdfDocument::MetaDataField field ) const

Returns the meta data of the document for the given field .

[invokable] QString QPdfDocument:: pageLabel ( int page )

返回 page number to be used for display purposes.

For example, a document may have multiple sections with different numbering. Perhaps the preface uses roman numerals, the body starts on page 1, and the appendix starts at A1. Whenever a PDF viewer shows a page number, to avoid confusing the user it should be the same "number" as is printed on the corner of the page, rather than the zero-based page index that we use in APIs (assuming the document author has made the page labels match the printed numbers).

If the document does not have custom page numbering, this function returns page + 1 .

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

[invokable] QSizeF QPdfDocument:: pagePointSize ( int page ) const

Returns the size of page page in points (1/72 of an inch).

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

QImage QPdfDocument:: render ( int page , QSize imageSize , QPdfDocumentRenderOptions renderOptions = QPdfDocumentRenderOptions())

渲染 page 成 QImage 的大小 imageSize according to the provided renderOptions .

Returns the rendered page or an empty image in case of an error.

注意：若 imageSize does not match the aspect ratio of the page in the PDF document, the page is rendered scaled, so that it covers the complete imageSize .

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