Web part in only Document Library pages

I've built a web part for SharePoint 2010.

Using SharePoint Designer I've got it to work on every page within the site, but then I realized that I only want it to work when users navigate document libraries.

Is there any way t开发者_C百科o do that? If not, how can I check that condition from the web part?

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Using SharePoint Designer I've got it to work on every page within the site

Does this mean you have embedded it in the master page?

A quick and dirty way; you could check the url for /Forms/ and only show it then.