QXmlFormatter ¶

概要 ¶

详细描述 ¶

QXmlFormatter 是子类化的 QXmlSerializer that formats the XML output to make it easier for humans to read.

QXmlSerializer outputs XML without adding unnecessary whitespace. In particular, it does not add newlines and indentation. To make the XML output easier to read, QXmlFormatter adds newlines and indentation by adding, removing, and modifying sequence nodes that only consist of whitespace. It also modifies whitespace in other places where it is not significant; e.g., between attributes and in the document prologue.

For example, where the base class QXmlSerializer would output this:

<Code snippet "/tmp/snapshot-qt5full-5.15.0/qt5/qtbase/patternist/notIndented.xml" not found>
											

QXmlFormatter outputs this:

<Code snippet "/tmp/snapshot-qt5full-5.15.0/qt5/qtbase/patternist/indented.xml" not found>
											

If you just want to serialize your XML in a human-readable format, use QXmlFormatter as it is. The default indentation level is 4 spaces, but you can set your own indentation value setIndentationDepth() .

newlines and indentation added by QXmlFormatter are suitable for common formats, such as XHTML, SVG, or Docbook, where whitespace is not significant. However, if your XML will be used as input where whitespace is significant, then you must write your own subclass of QXmlSerializer or QAbstractXmlReceiver .

Note that using QXmlFormatter 而不是 QXmlSerializer will increase computational overhead and document storage size due to the insertion of whitespace.

Note also that the indentation style used by QXmlFormatter remains loosely defined and may change in future versions of Qt. If a specific indentation style is required then either use the base class QXmlSerializer directly, or write your own subclass of QXmlSerializer or QAbstractXmlReceiver . Alternatively, you can subclass QXmlFormatter and reimplement the callbacks there.

QXmlQuery query;
query.setQuery("doc('index.html')/html/body/p[1]");
QXmlFormatter formatter(query, myOutputDevice);
formatter.setIndentationDepth(2);
query.evaluateTo(&formatter);
											

class QXmlFormatter ( query , outputDevice ) ¶

param query

QXmlQuery

param outputDevice

QIODevice

Constructs a formatter that uses the name pool and message handler in query , and writes the result to outputDevice as formatted XML.

outputDevice is passed directly to QXmlSerializer ‘s constructor.

另请参阅

QXmlSerializer

PySide2.QtXmlPatterns.QXmlFormatter. indentationDepth ( ) ¶

返回类型

int

Returns the number of spaces QXmlFormatter will output for each indentation level. The default is four.

另请参阅

setIndentationDepth()

PySide2.QtXmlPatterns.QXmlFormatter. setIndentationDepth ( depth ) ¶

参数

depth – int

集 depth to be the number of spaces QXmlFormatter will output for level of indentation. The default is four.

另请参阅

indentationDepth()