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XmlChan - I/O Channel using XML to represent Objects

Description:
A XmlChan is a specialised form of Channel which supports XML I/O operations. Writing an Object to an XmlChan (using astWrite) will, if the Object is suitable, generate an XML description of that Object, and reading from an XmlChan will create a new Object from its XML description.

Normally, when you use an XmlChan, you should provide "source" and "sink" functions which connect it to an external data store by reading and writing the resulting XML text. These functions should perform any conversions needed between external character encodings and the internal ASCII encoding. If no such functions are supplied, a Channel will read from standard input and write to standard output.

Alternatively, an XmlChan can be told to read or write from specific text files using the SinkFile and SourceFile attributes, in which case no sink or source function need be supplied.

Constructor Function:
astXmlChan
Inheritance
The XmlChan class inherits from the Channel class.
Attributes
In addition to those attributes common to all Channels, every XmlChan also has the following attributes:

Functions
The XmlChan class does not define any new functions beyond those which are applicable to all Mappings.


next up previous 264
Next: ZoomMap - Zoom coordinates about the origin
Up: AST Class Descriptions
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AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. Warren-Smith & D.S. Berry
7th December 2012
E-mail:starlink@jiscmail.ac.uk

Copyright (C) 2012 Science \& Technology Facilities Council