You can preset
the content to a certain extend by setting the TitleToShare and UrlToShare properties. Please keep in mind that once the given social network receives the URL it is up to its own logic to request the page and determine the exact content from it that will be shown. Usually this is set by using certain meta tags from the OpenGraph
protocol which should be defined by the developer.
We are currently working on a client-side API that will allow you to change the shared strings (URL and title) and this functionality will be available shortly with the Q1 2012 BETA release.
If this is not what you intend/need please explain your scenario in greater detail so we can understand it better and see how it fits in the concept of the control.
the Telerik team
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