/// <summary>
/// Specifies flags for the attributes of a method implementation.
/// </summary>
[ComVisible(true)]
[__DynamicallyInvokable]
[Serializable]
public enum MethodImplAttributes
{
[__DynamicallyInvokable] IL = 0,
[__DynamicallyInvokable] Managed = 0,
[__DynamicallyInvokable] Native = 1,
[__DynamicallyInvokable] OPTIL = 2,
[__DynamicallyInvokable] CodeTypeMask = 3,
[__DynamicallyInvokable] Runtime = 3,
[__DynamicallyInvokable] ManagedMask = 4,
[__DynamicallyInvokable] Unmanaged = 4,
[__DynamicallyInvokable] NoInlining = 8,
[__DynamicallyInvokable] ForwardRef = 16,
[__DynamicallyInvokable] Synchronized = 32,
[__DynamicallyInvokable] NoOptimization = 64,
[__DynamicallyInvokable] PreserveSig = 128,
[ComVisible(false), __DynamicallyInvokable] AggressiveInlining = 256,
[__DynamicallyInvokable] InternalCall = 4096,
MaxMethodImplVal = 65535,
}
为什么这个枚举没有标记FlagsAttribute?它可以在MSDN上找到的所有示例中像位域一样使用,并且MSDN上属性的大多数指南都符合此定义。
MethodBuilder.SetImplementationFlags()甚至暗示它被用作除了MSDN示例代码之外的[Flags]标记的枚举。
答案 0 :(得分:0)
您始终可以在这些枚举上使用位操作,即使它们未标记为FlagsAttribute
。事实上,FlagsAttribute
仅用于.ToString
方法,使输出字符串更漂亮。
enum DataFlag
{
Private = 1,
Important = 2,
Persistant = 4
}
var flag = DataFlag.Private | DataFlag.Persistant;
var test = flag.HasFlag(DataFlag.Private); //True with/without FlagAttribute
var stringResult = flag.ToString(); // with FlagAttribute: Private, Persistant
// without : 5
顺便说一句,此枚举有MethodImplAttributes.IL = 0
,即使您有.ToString
,它也不会出现在FlagsAttribute
输出中,并且一些字段具有相同的值,这可能会导致意外行为字符串结果。一般来说,使用FlagsAttribute
标记此属性是正确和良好的做法。