<ExtensionAttribute()>
Public Overloads Shared Function First(Of TResult)( _
   ByVal source As IEntityScalarQuery(Of TResult), _
   Optional ByVal userCallback As Action(Of EntityScalarQueryOperation(Of TResult)), _
   Optional ByVal userState As Object _
) As EntityScalarQueryOperation(Of TResult)

Dim source As IEntityScalarQuery(Of TResult)
Dim userCallback As Action(Of EntityScalarQueryOperation(Of TResult))
Dim userState As Object
Dim value As EntityScalarQueryOperation(Of TResult)
 
value = EntityScalarAsyncExtensions.First(Of TResult)(source, userCallback, userState)

[ExtensionAttribute()]
public static EntityScalarQueryOperation<TResult> First<TResult>( 
   IEntityScalarQuery<TResult> source,
   Action<EntityScalarQueryOperation<TResult>> userCallback,
   object userState
)

[ExtensionAttribute()]
public:
static EntityScalarQueryOperation<TResult^>^ Firstgeneric<typename TResult>
( 
   IEntityScalarQuery<TResult^>^ source,
   Action<EntityScalarQueryOperation<TResult^>^>^ userCallback,
   Object^ userState
) 

public void AsyncFirst() {
  var op = _entityManager.Employees.AsScalarAsync().First();
  op.Completed += (o, e) => {
    var emp = e.Result;
  };
}