class QDomImplementation

The QDomImplementation class provides information about the features of the DOM implementation. More

Synopsis

Methods

Static functions

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description

This class describes the features that are supported by the DOM implementation. Currently the XML subset of DOM Level 1 and DOM Level 2 Core are supported.

Normally you will use the function implementation() to get the implementation object.

You can create a new document type with createDocumentType() and a new document with createDocument() .

For further information about the Document Object Model see Level 1 and Level 2 Core . For a more general introduction of the DOM implementation see the QDomDocument documentation.

The QDom classes have a few issues of nonconformance with the XML specifications that cannot be fixed in Qt 4 without breaking backward compatibility. The Qt XML Patterns module and the QXmlStreamReader and QXmlStreamWriter classes have a higher degree of a conformance.

See also

hasFeature()

class InvalidDataPolicy

This enum specifies what should be done when a factory function in QDomDocument is called with invalid data.

Constant

Description

QDomImplementation.AcceptInvalidChars

The data should be stored in the DOM object anyway. In this case the resulting XML document might not be well-formed. This is the default value and QDom’s behavior in Qt < 4.1.

QDomImplementation.DropInvalidChars

The invalid characters should be removed from the data.

QDomImplementation.ReturnNullNode

The factory function should return a null node.

__init__()

Constructs a QDomImplementation object.

__init__(implementation)
Parameters:

implementationQDomImplementation

Constructs a copy of implementation.

createDocument(nsURI, qName, doctype)
Parameters:
Return type:

QDomDocument

Creates a DOM document with the document type doctype. This function also adds a root element node with the qualified name qName and the namespace URI nsURI.

createDocumentType(qName, publicId, systemId)
Parameters:
  • qName – str

  • publicId – str

  • systemId – str

Return type:

QDomDocumentType

Creates a document type node for the name qName.

publicId specifies the public identifier of the external subset. If you specify an empty string (QString()) as the publicId, this means that the document type has no public identifier.

systemId specifies the system identifier of the external subset. If you specify an empty string as the systemId, this means that the document type has no system identifier.

Since you cannot have a public identifier without a system identifier, the public identifier is set to an empty string if there is no system identifier.

DOM level 2 does not support any other document type declaration features.

The only way you can use a document type that was created this way, is in combination with the createDocument() function to create a QDomDocument with this document type.

In the DOM specification, this is the only way to create a non-null document. For historical reasons, Qt also allows to create the document using the default empty constructor. The resulting document is null, but becomes non-null when a factory function, for example createElement() , is called. The document also becomes non-null when setContent() is called.

See also

createDocument()

hasFeature(feature, version)
Parameters:
  • feature – str

  • version – str

Return type:

bool

The function returns true if QDom implements the requested version of a feature; otherwise returns false.

The currently supported features and their versions:

Feature

Version

XML

1.0

static invalidDataPolicy()
Return type:

InvalidDataPolicy

Returns the invalid data policy, which specifies what should be done when a factory function in QDomDocument is passed invalid data.

isNull()
Return type:

bool

Returns false if the object was created by implementation() ; otherwise returns true.

__ne__(other)
Parameters:

otherQDomImplementation

Return type:

bool

Returns true if other and this DOM implementation object were created from different QDomDocuments; otherwise returns false.

__eq__(other)
Parameters:

otherQDomImplementation

Return type:

bool

Returns true if other and this DOM implementation object were created from the same QDomDocument ; otherwise returns false.

static setInvalidDataPolicy(policy)
Parameters:

policyInvalidDataPolicy

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

Sets the invalid data policy, which specifies what should be done when a factory function in QDomDocument is passed invalid data.

The policy is set for all instances of QDomDocument which already exist and which will be created in the future.

def XML_snippet_main():

doc = QDomDocument()
impl = QDomImplementation()
# This will create the element, but the resulting XML document will
# be invalid, because '~' is not a valid character in a tag name.
impl.setInvalidDataPolicy(QDomImplementation.AcceptInvalidChars)
elt1 = doc.createElement("foo~bar")
# This will create an element with the tag name "foobar".
impl.setInvalidDataPolicy(QDomImplementation.DropInvalidChars)
elt2 = doc.createElement("foo~bar")
# This will create a null element.
impl.setInvalidDataPolicy(QDomImplementation.ReturnNullNode)
elt3 = doc.createElement("foo~bar")