移位的方式产生枚举不重复值

[Flags]
public enum CefContextMenuMediaStateFlags
{
None = 0,
Error = 1 << 0,
Paused = 1 << 1,
Muted = 1 << 2,
Loop = 1 << 3,
CanSave = 1 << 4,
HasAudio = 1 << 5,
HasVideo = 1 << 6,
ControlRootElement = 1 << 7,
CanPrint = 1 << 8,
CanRotate = 1 << 9,
}

<<操作符，向左移位。。

2 的0次方 2 的一次方