Webparts on a layoutpage which is provisioned several times
By Anatoly Mironov
It is pretty easy to add webparts to a layout page. Just define the webparts in the corresponding Elements.xml file. Like you do in onet.xml. It works fine if you provision just a single page with this layout on a web. If you have multiple pages that use the same page layout (e.g. in WCM). The trick is to use the attribute IgnoreIfAlreadyExists in the File tag:
IgnoreIfAlreadyExists="True"
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Webpart in a reusable user control « Sharepoint. Kunskap. Upptäckter på resan. - Sep 1, 2011
[…] my previous post I wrote about using IgnoreIfAlreadyExists=”True” for preventing of adding webparts multiple times. It works fine until you redeploy your project. Another approach is to use a user control with you […]