I have a C++ project in which I am using Microsoft XmlLite for parsing several XML files. Now I have a new file that I need to parse and I have an XSD schema for it. I know there are many C++ XML binding tools out there, but all I have found so far require me to include yet another XML parsing library, which I would like to avoid. Hence my question: is there any open source or commercial tool that generates C++ XML bindings based on Microsoft XmlLite?
CodeSynthesis seems to be the closest tool which will provide in-memory XML data binding to integrate with XMLLite.
The C++/Tree mapping generates C++ classes that represent data types defined in XML Schema, a set of parsing functions that convert XML documents to a tree-like in-memory object model, and a set of serialization functions that convert the object model back to XML.
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I am working with potentially "large" xml files where my application only cares about a very small subset of the data contained in the file. So I was hoping to avoid loading the entire xml document into DOM.
I have been successfully using Apache Xerces C++ with the Sax2 api to extract data directly from an xml file contained in a zip archive, using custom implementations of xercesc::BinInputStream and xercesc::InputSource
However, now we want to apply modifications to a small subset of the nodes in the xml document (reading the original, and applying changes into a new xml file in a new zip archive). I was hoping to avoid loading the entire document into DOM just to modify a few nodes.
It would be nice to leverage the work I've already done with SAX2, but it appears that the SAX2 api is primarily oriented around reading documents. I could handle all SAX2 events, and write the information out to the new file as they occur, but I'm having difficulty locating xerces api functionality that would, for example, aid with handling xml entities (I really don't want to rewrite e.g. xml entity handling myself!) and other encoding issues.
I also noticed that xerces provides a xercesc::BinOuputStream (which would appear to be what I would want to derive from in order to directly serialize to a zip archive), but I haven't found a place where I could plug such a custom output stream into the xerces api. I also haven't been able to locate a corresponding output analogue for xercesc::InputSource.
Does xerces c++ provide any native functionality for writing xml documents in a streaming fashion?
I am working in Ubuntu. I have a .h file with a class and a lot of nested classes. I would like to create an XML file from an object. Can someone please give me a library that creates XML files, serializes, and deserializes objects? I am compiling with g++.
Try libxml2.
But it seems like you want to serialize and desirialize an object from and to XML. Boost::serialization might come in handy. it also supports serialization from and to XML.
Here you can find an example for Boost::serialization with XML.
If you want to handle XML in C++ you may have a look at these projects
http://xmlsoft.org/
http://www.grinninglizard.com/tinyxml/
http://xerces.apache.org/xerces-c/
It doesn't serialize with XML (which I consider a feature, personally), but Google protocol buffers does a good job of serializing (in a binary format) objects that are defined in the .proto language.
You may want to explore the XML Data Binding. The main idea is that given an xml schema the data binding software generates a class hierarchy corresponding to the schema, and the code to serialize / unserialize (called marshal / unmarshal). There are several tools that can do this, gsoap is a free one, xmlSpy is one of the commercial ones.
What you describe is an XML data binding for C++. There are several tools for what you want to do, see e.g. XML Data Binding Tools. I've used gSOAP for several C++ projects, including starting from C++ files with classes which is really nice (other tools force you to start from XML schemas or WSDLs). With gSOAP I have been able to generate XML schemas and XML, see e.g. map C/C++ types to XML schema.
A super-lightweight, simple xml library is pugixml.
Though keep in mind that C++ does not have the reflection capabilities that .NET has. No library will generate the serialization/deserialization code for you (which I guess you hoped for).
I am writing a Word add-in which is supposed to store some own XML data per document using Word object model and its CustomXMLPart. The problem I am now facing is the lack of IStream-like functionality for reading/writing XML to/from a CustomXMLPart. It only provides BSTR interface and I am puzzled how to handle UTF-8 XMLs with BSTRs. To my understanding an UTF-8 XML file should really never have to undergo this sort of Unicode conversion. I am not sure what to expect as a result here.
Is there another way of using Word automation interfaces to store arbitrary custom information inside a DOCX file?
The "package" is an OPC document (Open Packaging Convention), which is basically a structured zip folder with a different extension (e.g. .pptx, .docx, .xps, etc.). You can get that file in stream and manipulate it any which way you like - but not artibitrarily. It will not be recognized as valid docx if you put things in the wrong places (not just xml elements, but also files in the folders inside the zip file). But if you're just talking "artibitrary" meaning CustomXMLPart, then that's okay.
This is a good kicker page to learn more about the Open XML SDK and if you're up to it, which allows for somewhat easier access to the file formats than using (.NET) System.IO.Packaging or a third-party zip library. To go deeper, grab the eBook (free) Open XML Explained.
With the Open XML SDK (again, this can all be done without the SDK) in .NET, this is what you'll want to do: How to: Insert Custom XML to an Office Open XML Package by Using the Open XML API.
I have a couple of questions about XML.
Can XML be used for normal c++ application instead of using a text file ?
If so, does this method have advantages?
and finally, how can I use XML to store data? what tools are needed?
Regards.
You can use XML for storing information - it's less Human readable than a text file, but can be more easily communicated with other systems and coding languages.
If all you need is a few text/numeric properties, stick to a property file.
If you need a mix of configuration options, and you want to use validation (can be accomplished using XML schema), automatic modification (e.g. XSL transformations) or communicate it easily with Web Services, than XML is useful.
If you want to store binary data, XML is probably not that answer. Though you can store it in a filesystem and use the XML for the metadata (i.e. where each file is located).
Take a look at Apache Xerces-C for C++ XML code - http://xerces.apache.org/xerces-c/
XML can be parsed as a text file by your application. There are libraries available.
Advantage: the files can be exchanged with other applications more easily, especially if you provide an XML-schema file.
Storing data in XML can be done with boost.serialization
It depends of the kind of data you want to read/write, but XML is generally a good way to go for storing structured and hierarchical datas.
You can use librairies such as TinyXML to easily parse and write XML files in C++.
The main drawback is that XML is verbose ; that's why you can also use an alternative such as JSON to store your datas.
I am using C++ from Mingw, which is the windows version of GNC C++.
What I want to do is: serialize C++ object into an XML file and deserialize object from XML file on the fly. I check TinyXML. It's pretty useful, and (please correct me if I misunderstand it) it basically add all the nodes during processing, and finally put them into a file in one chunk using TixmlDocument::saveToFile(filename) function.
I am working on real-time processing, and how can I write to a file on the fly and append the following result to the file?
Thanks.
BOOST has a very nice Serialization/Deserialization lib BOOST.Serialization.
If you stream your objects to a boost xml archive it will stream them in xml format.
If xml is to big or to slow you only need to change the archive in a text or binary archive to change the streaming format.
Here is a better example of C++ object serialization:
http://www.codeproject.com/KB/XML/XMLFoundation.aspx
I notice that each TiXmlBase Class has a Print method and also supports streaming to strings and streams.
You could walk the new parts of the document in sequence and output those parts as they are added, maybe?
Give it a try.....
Tony
I've been using gSOAP for this purpose. It is probably too powerful for just XML serialization, but knowing it can do much more means I do not have to consider other solutions for more advanced projects since it also supports WSDL, SOAP, XML-RPC, and JSON. Also suitable for embedded and small devices, since XML is simply a transient wire format and not kept in a DOM or something memory intensive.