XML editor

An XML editor is a markup language editor with added functionality to facilitate the editing of XML. This can be done using a plain text editor, with all the code visible, but XML editors have added facilities like tag completion and menus and buttons for tasks that are common in XML editing, based on data supplied with document type definition (DTD) or the XML tree.

There are also graphical XML editors that hide the code in the background and present the content to the user in a more user-friendly format, approximating the rendered version or editing forms. This is helpful for situations where people who are not fluent in XML code need to enter information in XML based documents such as time sheets and expenditure reports. And even if the user is familiar with XML, use of such editors, which take care of syntax details, is often faster and more convenient.

An XML editor goes beyond the syntax highlighting offered by many plaintext editors and generic source code editors, verifying the XML source based on an XML schema or XML DTD, and some can do it as the document is being edited in real time. Other features of an editor designed specifically for editing XML might include element word completion and automatic appending of a closing tag whenever an opening tag is entered. These features can help to prevent typographically originating errors in the XML code. Some XML editors provide for the ability to run an XSLT transform, or series of transforms, over a document. Some of the larger XML packages even offer XSLT debugging features and XSL-FO processors for generation of PDF files from documents.

Text XML editors generally provide features dealing with working with element tags. Syntax highlighting is a basic standard of any XML editor; that is, they color element text differently from regular text. Element and attribute completion based on a DTD or schema is also available from many text XML editors. Displaying line numbers is also a common and useful feature, as is providing the ability to reformat a document to conform to a particular style of indenture.

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