`#ifdef`'s always seem to end up being messy. It's not ideal, though we could do something like this:

```c#
#if NET45
	private async void CopySourceToClipBoardAsyncClick(object sender, EventArgs e)
	{
		// NOTE: If you don't need to be able to deploy to .NET 4.0, you can use 4.5 await/async

		await CopySourceToClipboardAsync45();
	}
#else
	private void CopySourceToClipBoardAsyncClick(object sender, EventArgs e)
	{
		CopySourceToClipboardAsync40();
	}
#endif
```