Apps for Office: Work with custom XML parts

?This sample writes user-specified text to a custom XML part that is bound to a content control within a Word 2013 document.

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Apps for Office: Work with custom XML parts

Content Control Event Model in Word 2007

New in Word 2007, content controls can be inserted into a document to provide more structure and control—for example when you have a section of the document that you want to allow the user to put a picture into or pick a value from a drop-down list. There are eight content controls: rich text, plain text, picture, combo box, drop-down list, date picker, group, and building block gallery

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Content Control Event Model in Word 2007