using enum value in cs?

How do you use an enum value in cs? Here's a function in one of the prime31 social networking plugins that asks for an enumerated value.

Here's the documentation from prime31 // Reauthorizes with the requested publish permissions and audience public static void reauthorizeWithPublishPermissions( string[] permissions, FacebookSessionDefaultAudience defaultAudience )

Here's the documentation from facebook

Typedefs FBSessionDefaultAudience enum

 Passed to open to indicate which default audience to use for sessions that post data to Facebook.
 typedef enum {
 FBSessionDefaultAudienceNone = 0,
 FBSessionDefaultAudienceOnlyMe = 10,
 FBSessionDefaultAudienceFriends = 20,
 FBSessionDefaultAudienceEveryone = 30,
 } FBSessionDefaultAudience; 

Here's my attempt
var permissions = new string[] {"publish_actions" }; FacebookBinding.reauthorizeWithPublishPermissions(permissions,FBSessionDefaultAudienceFriends);

How do I enter the FBSessionDefaultAudience value. I've tried the following and none of them work and give an error of not found in current context.
1. FBSessionDefaultAudienceFriends
2. FBSessionDefaultAudience.FBSessionDefaultAudienceFriends
3. 20