'宣言
Public Shared Function SelectMany
(Of ,)( _
ByVal As System.Collections.Generic.IEnumerable(Of TSource), _
ByVal As System.Func(Of TSource,IEnumerable(Of TResult)) _
) As System.Collections.Generic.IEnumerable(Of TResult)
public static System.Collections.Generic.IEnumerable<TResult> SelectMany<,>(
System.Collections.Generic.IEnumerable<TSource> ,
System.Func<TSource,IEnumerable<TResult>>
)