What part exactly do you want an equivalent for? It cannot be "the whole thing", because this javascript is using jQuery, which means that it is running in a browser. But you cannot execute C# directly on a browser, so there cannot be a direct equivalent in C# for this javascript.
So we are going to need a more precise description of what you are trying to accomplish and how and where, in order to find some way to do such a thing in C#. Or, alternatively, if you are just looking for a syntactical equivalent in C# for one particular language construction in your javascript, please point us to the specific part that you have in mind.