Chod,
If I understand you correctly, ideally you would like to be able to set the various resources that your sitemapnode might use through code. Unfortunately, this isn't possible. The implicitResourceKey and explicitResourceKeys parameters are meant to be used in conjunction with with the existing resources system.
These parameters might be more easily understood with comparable examples in XmlSiteMapProvider.
<siteMapNode resourceKey="foo" /> <-- this sets the implicitResourceKey parameter to "foo"
<siteMapNode title="$resources: k,v" /> <-- this sets an entry in the explicitResourceKey's NameValue collection. "title" -> "k.v"
--
Danny
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