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Pre-converters are services that preprocess the internal XML before the XSLT rendering occurs. It can be useful if you need to manipulate the data stored in eZXML.

An example of use is what is done for internal links. Indeed, internal location or content are linked by their locationId/contentId which need to be transformed into a usable URIin the EmbedTagBundle for videos : video links are transformed in embed links.

Pre-converters receive the whole DOMDocument object for the current field. So you can easily do XPath queries and do some DOM manipulation against it.

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