How do I get my selected gridview rows into a javascript variable?

I use ASP.NET C# MVC3 with razor templates and I want to know the following:

I have a devexpress gridview in which I can select rows.
When selected I want to pass them into a javascript variable. How do I do this?
And what if I have selected multiple rows at the same time, can I get them in an array or something?

Regards,

Marco

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