The QDomImplementation class provides information about the features of the DOM implementation. 更多...
The QDomImplementation class provides information about the features of the DOM implementation.
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.
通常，使用函数 QDomDocument.implementation () to get the implementation object.
可以创建新的文档类型采用 createDocumentType () and a new document with createDocument ().
有关文档对象模型的进一步信息，见 级别 1 and 级别 2 核心 . For a more general introduction of the DOM implementation see the QDomDocument 文档编制。
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 QtXmlPatterns module and the QXmlStreamReader and QXmlStreamWriter classes have a higher degree of a conformance.
This enum specifies what should be done when a factory function in QDomDocument is called with invalid data.
| 常量 | 值 | 描述 |
|---|---|---|
| QDomImplementation.AcceptInvalidChars | 0 | 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 | 1 | The invalid characters should be removed from the data. |
| QDomImplementation.ReturnNullNode | 2 | The factory function should return a null 节点。 |
另请参阅 setInvalidDataPolicy () and invalidDataPolicy ().
构造 QDomImplementation 对象。
构造副本为 x .
创建的 DOM (文档对象模型) 文档具有文档类型 doctype . This function also adds a root element node with the qualified name qName 和名称空间 URI nsURI .
创建文档类型节点为名称 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 标识符。
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 QDomDocument.createElement (), is called. The document also becomes non-null when setContent() is called.
另请参阅 createDocument ().
The function returns true if QDom implements the requested version of a feature ；否则返回 false。
目前支持的特征及其版本：
| Feature | 版本 |
|---|---|
| XML | 1.0 |
Returns the invalid data policy, which specifies what should be done when a factory function in QDomDocument is passed invalid data.
警告： 此函数不 可重入 .
该函数在 Qt 4.1 引入。
另请参阅 setInvalidDataPolicy () and InvalidDataPolicy .
Returns false if the object was created by QDomDocument.implementation (); otherwise returns true.
Sets the invalid data policy, which specifies what should be done when a factory function in QDomDocument is passed invalid data.
policy is set for all instances of QDomDocument which already exist and which will be created in the future.
QDomDocument doc; QDomImplementation impl; // 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.AcceptInvalidData); QDomElement elt1 = doc.createElement("foo~bar"); // This will create an element with the tag name "foobar". impl.setInvalidDataPolicy(QDomImplementation.DropInvalidData); QDomElement elt2 = doc.createElement("foo~bar"); // This will create a null element. impl.setInvalidDataPolicy(QDomImplementation.ReturnNullNode); QDomElement elt3 = doc.createElement("foo~bar");
警告： 此函数不 可重入 .
该函数在 Qt 4.1 引入。
另请参阅 invalidDataPolicy () and InvalidDataPolicy .
