blocks|key|1092397|text|几年后，随着经验的增加，我对单个位值的最终答案是从最低位移动到最高位，这是Jeff+Mercado内部例程的一个轻微变体：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092398|public+static+IEnumerable<Enum>+GetUniqueFlags(this+Enum+flags)
{
++++ulong+flag+=+1;
++++foreach+(var+value+in+Enum.GetValues(flags.GetType()).Cast<Enum>())
++++{
++++++++ulong+bits+=+Convert.ToUInt64(value);
++++++++while+(flag+<+bits)
++++++++{
++++++++++++flag+<<=+1;
++++++++}

++++++++if+(flag+==+bits+&&+flags.HasFlag(value))
++++++++{
++++++++++++yield+return+value;
++++++++}
++++}
}|code-block|syntax|javascript|1092399|它似乎是有效的，尽管我在几年前就反对过，但我在这里使用HasFlag，因为它比使用逐位比较容易理解得多，并且速度差异对于我将要做的任何事情都是微不足道的。(从那时起，他们完全有可能提高了HasFlags的速度，就我所知……我还没有测试过。)|1092400|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Coming back at this a few years later, with a bit more experience, my ultimate answer for single-bit values only, moving from lowest bit to highest bit, is a slight variant of Jeff Mercado's inner routine:

<pre><code>public static IEnumerable&lt;Enum&gt; GetUniqueFlags(this Enum flags)
{
 ulong flag = 1;
 foreach (var value in Enum.GetValues(flags.GetType()).Cast&lt;Enum&gt;())
 {
 ulong bits = Convert.ToUInt64(value);
 while (flag &lt; bits)
 {
 flag &lt;&lt;= 1;
 }

 if (flag == bits &amp;&amp; flags.HasFlag(value))
 {
 yield return value;
 }
 }
}
</code></pre>

It seems to work, and despite my objections of some years ago, I use HasFlag here, since it's far more legible than using bitwise comparisons and the speed difference is insignificant for anything I'll be doing. (It's entirely possible they've improved the speed of HasFlags since then anyway, for all I know...I haven't tested.)

blocks|key|1092090|text|static+IEnumerable<Enum>+GetFlags(Enum+input)
{
++++foreach+(Enum+value+in+Enum.GetValues(input.GetType()))
++++++++if+(input.HasFlag(value))
++++++++++++yield+return+value;
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1092091|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>static IEnumerable&lt;Enum&gt; GetFlags(Enum input)
{
 foreach (Enum value in Enum.GetValues(input.GetType()))
 if (input.HasFlag(value))
 yield return value;
}
</code></pre>

blocks|key|877674|text|以下是Linq对该问题的解决方案。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|877675|public+static+IEnumerable<Enum>+GetFlags(this+Enum+e)
{
++++++return+Enum.GetValues(e.GetType()).Cast<Enum>().Where(e.HasFlag);
}|code-block|syntax|javascript|877676|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Here is a Linq solution to the problem.

<pre><code>public static IEnumerable&lt;Enum&gt; GetFlags(this Enum e)
{
 return Enum.GetValues(e.GetType()).Cast&lt;Enum&gt;().Where(e.HasFlag);
}
</code></pre>

blocks|key|1092582|text|不再使用@Greg的方法，但从C#+7.3添加了一个新特性，即Enum约束：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1092583|public+static+IEnumerable<T>+GetUniqueFlags<T>(this+T+flags)
++++where+T+:+Enum++++//+New+constraint+for+C#+7.3
{
++++foreach+(Enum+value+in+Enum.GetValues(flags.GetType()))
++++++++if+(flags.HasFlag(value))
++++++++++++yield+return+(T)value;
}|code-block|syntax|javascript|1092584|新的约束允许它成为一个扩展方法，而不必通过(int)(object)e转换，我可以使用HasFlag方法并从value直接转换为T。|1092585|C#+7.3还添加了对for委托和unmanaged的约束。|1092586|entityMap^0|V|4|0|0|L|E|17|7|1I|5|1S|1|0|H|9|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@$9|V|A|W|B|C]|$9|X|A|Y|B|C]|$9|Z|A|10|B|C]|$9|11|A|12|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|13|8|@$9|14|A|15|B|C]]|D|@]|E|$]]|$1|O|3|-4|5|6|7|16|8|@]|D|@]|E|$]]]|P|$]]

Going off of @Greg's method, but adding a new feature from C# 7.3, the <code>Enum</code> constraint:
<pre><code>public static IEnumerable&lt;T&gt; GetUniqueFlags&lt;T&gt;(this T flags)
 where T : Enum // New constraint for C# 7.3
{
 foreach (Enum value in Enum.GetValues(flags.GetType()))
 if (flags.HasFlag(value))
 yield return (T)value;
}
</code></pre>
The new constraint allows this to be an extension method, without having to cast through <code>(int)(object)e</code>, and I can use the <code>HasFlag</code> method and cast directly to <code>T</code> from <code>value</code>.
C# 7.3 also added constraints to for delegates and <code>unmanaged</code>.

blocks|key|1092244|text|我所做的是改变我的方法，而不是键入方法的输入参数作为enum类型，而是键入为enum类型的数组(MyEnum[]+myEnums)，这样我只需在循环中使用switch语句迭代数组。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1092245|entityMap^0|Q|4|12|4|1C|G|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|O|8|@]|D|@]|E|$]]]|G|$]]

What I did was change my approach, instead of typing the input parameter of the method as the <code>enum</code> type, I typed it as an array of the <code>enum</code> type (<code>MyEnum[] myEnums</code>), this way I just iterate through the array with a switch statement inside the loop.

blocks|key|1092788|text|使用新的Enum约束和泛型来防止强制转换的扩展方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092789|public+static+class+EnumExtensions
{
++++public+static+T[]+GetFlags<T>(this+T+flagsEnumValue)+where+T+:+Enum
++++{
++++++++return+Enum
++++++++++++.GetValues(typeof(T))
++++++++++++.Cast<T>()
++++++++++++.Where(e+=>+flagsEnumValue.HasFlag(e))
++++++++++++.ToArray();
++++}
}|code-block|syntax|javascript|1092790|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Extension method using the new Enum constraint and generics to prevent casting:
<pre><code>public static class EnumExtensions
{
 public static T[] GetFlags&lt;T&gt;(this T flagsEnumValue) where T : Enum
 {
 return Enum
 .GetValues(typeof(T))
 .Cast&lt;T&gt;()
 .Where(e =&gt; flagsEnumValue.HasFlag(e))
 .ToArray();
 }
}
</code></pre>

blocks|key|878090|text|我继续努力使代码更简短，这是我例程的最新版本。(我是OP...long的故事。)如前所述，这将忽略None和多位值。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|878091|请注意，这使用了枚举约束和var模式，因此至少需要C#+7.3。|878092|public+static+IEnumerable<T>+GetUniqueFlags<T>(this+T+value)
++++where+T+:+Enum
{
++++var+valueLong+=+Convert.ToUInt64(value,+CultureInfo.InvariantCulture);
++++foreach+(var+enumValue+in+value.GetType().GetEnumValues())
++++{
++++++++if+(
++++++++++++enumValue+is+T+flag+//+cast+enumValue+to+T
++++++++++++&&+Convert.ToUInt64(flag,+CultureInfo.InvariantCulture)+is+var+bitValue+//+convert+flag+to+ulong
++++++++++++&&+(bitValue+&+(bitValue+-+1))+==+0+//+is+this+a+single-bit+value?
++++++++++++&&+(valueLong+&+bitValue)+!=+0+//+is+the+bit+set?
+++++++++++)
++++++++{
++++++++++++yield+return+flag;
++++++++}
++++}
}|code-block|syntax|javascript|878093|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Continuing in my efforts to make the code shorter, this is my latest version of the routine. (I'm the OP...long story.) As discussed previously, this ignores None and multi-bit values.
Note that this uses an Enum constraint and a var pattern, so will require at least C# 7.3.
<pre><code>public static IEnumerable&lt;T&gt; GetUniqueFlags&lt;T&gt;(this T value)
 where T : Enum
{
 var valueLong = Convert.ToUInt64(value, CultureInfo.InvariantCulture);
 foreach (var enumValue in value.GetType().GetEnumValues())
 {
 if (
 enumValue is T flag // cast enumValue to T
 &amp;&amp; Convert.ToUInt64(flag, CultureInfo.InvariantCulture) is var bitValue // convert flag to ulong
 &amp;&amp; (bitValue &amp; (bitValue - 1)) == 0 // is this a single-bit value?
 &amp;&amp; (valueLong &amp; bitValue) != 0 // is the bit set?
 )
 {
 yield return flag;
 }
 }
}
</code></pre>

blocks|key|1092028|text|你不需要迭代所有的值。只需检查您的特定标志，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092029|if((myVar+&+FlagsEnum.Flag1)+==+FlagsEnum.Flag1)+
{
+++//do+something...
}|code-block|syntax|javascript|1092030|或者(正如pstrjds在评论中所说的)你可以像这样检查它的使用：|offset|length|1092031|if(myVar.HasFlag(FlagsEnum.Flag1))
{
+++//do+something...
}|1092032|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/users/416574/pstrjds^0|0|0|5|7|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@]|9|@$I|X|J|Y|1|Z]]|A|$]]|$1|K|3|L|5|D|7|10|8|@]|9|@]|A|$E|F]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]]]

You dont need to iterate all values. just check your specific flags like so:

<pre><code>if((myVar & FlagsEnum.Flag1) == FlagsEnum.Flag1) 
{
 //do something...
}
</code></pre>

or (as <a href="https://stackoverflow.com/users/416574/pstrjds">pstrjds</a> said in comments) you can check for use it like:

<pre><code>if(myVar.HasFlag(FlagsEnum.Flag1))
{
 //do something...
}
</code></pre>

blocks|key|1092182|text|对上面的答案并不满意，尽管它们只是个开始。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092183|在这里拼凑了一些不同的来源之后：|1092184|Previous+poster+in+this+thread's+SO+QnA|offset|length|1092185|Code+Project+Enum+Flags+Check+Post|1092186|Great+Enum+Utility|1092187|我创建了这个，所以让我知道你的想法。|1092188|参数：|1092189|bool+checkZero：告诉它允许0作为标志值。默认情况下，input+=+0返回空。|style|CODE|1092190|bool+checkFlags：告诉它检查Enum是否用[Flags]属性修饰。|1092191|PS。我现在没有时间来弄清楚checkCombinators+=+false算法，这将迫使它忽略任何枚举值，这些值是位的组合。|1092192|++++public+static+IEnumerable<TEnum>+GetFlags<TEnum>(this+TEnum+input,+bool+checkZero+=+false,+bool+checkFlags+=+true,+bool+checkCombinators+=+true)
++++{
++++++++Type+enumType+=+typeof(TEnum);
++++++++if+(!enumType.IsEnum)
++++++++++++yield+break;

++++++++ulong+setBits+=+Convert.ToUInt64(input);
++++++++//+if+no+flags+are+set,+return+empty
++++++++if+(!checkZero+&&+(0+==+setBits))
++++++++++++yield+break;

++++++++//+if+it's+not+a+flag+enum,+return+empty
++++++++if+(checkFlags+&&+!input.GetType().IsDefined(typeof(FlagsAttribute),+false))
++++++++++++yield+break;

++++++++if+(checkCombinators)
++++++++{
++++++++++++//+check+each+enum+value+mask+if+it+is+in+input+bits
++++++++++++foreach+(TEnum+value+in+Enum<TEnum>.GetValues())
++++++++++++{
++++++++++++++++ulong+valMask+=+Convert.ToUInt64(value);

++++++++++++++++if+((setBits+&+valMask)+==+valMask)
++++++++++++++++++++yield+return+value;
++++++++++++}
++++++++}
++++++++else
++++++++{
++++++++++++//+check+each+enum+value+mask+if+it+is+in+input+bits
++++++++++++foreach+(TEnum+value+in+Enum+<TEnum>.GetValues())
++++++++++++{
++++++++++++++++ulong+valMask+=+Convert.ToUInt64(value);

++++++++++++++++if+((setBits+&+valMask)+==+valMask)
++++++++++++++++++++yield+return+value;
++++++++++++}
++++++++}

++++}|code-block|syntax|javascript|1092193|这利用了我为使用yield+return+for+GetValues而更新的帮助器类Enum+found+here|1092194|public+static+class+Enum<TEnum>
{
++++public+static+TEnum+Parse(string+value)
++++{
++++++++return+(TEnum)Enum.Parse(typeof(TEnum),+value);
++++}

++++public+static+IEnumerable<TEnum>+GetValues()+++
++++{
++++++++foreach+(object+value+in+Enum.GetValues(typeof(TEnum)))
++++++++++++yield+return+((TEnum)value);
++++}
}++|1092195|最后，这里有一个使用它的例子：|1092196|++++private+List<CountType>+GetCountTypes(CountType+countTypes)
++++{
++++++++List<CountType>+cts+=+new+List<CountType>();

++++++++foreach+(var+ct+in+countTypes.GetFlags())
++++++++++++cts.Add(ct);

++++++++return+cts;
++++}|1092197|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/4717550/hasflag-not-recognizing-role-assignment|1|http://www.codeproject.com/Tips/194233/See-if-a-Flags-enum-is-valid?display=Print|2|http://devlicious.com/blogs/christopher_bennage/archive/2007/09/13/my-new-little-friend-enum-lt-t-gt.aspx|3^0|0|0|0|13|0|0|0|Y|1|0|0|I|2|0|0|0|0|E|K|1|X|9|0|0|F|L|4|S|7|0|E|O|0|0|8|C|P|9|16|F|3|0|0|0|0^^$0|@$1|2|3|4|5|6|7|1N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|1O|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|1P|8|@]|9|@$F|1Q|G|1R|1|1S]]|A|$]]|$1|H|3|I|5|6|7|1T|8|@]|9|@$F|1U|G|1V|1|1W]]|A|$]]|$1|J|3|K|5|6|7|1X|8|@]|9|@$F|1Y|G|1Z|1|20]]|A|$]]|$1|L|3|M|5|6|7|21|8|@]|9|@]|A|$]]|$1|N|3|O|5|6|7|22|8|@]|9|@]|A|$]]|$1|P|3|Q|5|6|7|23|8|@$F|24|G|25|R|S]|$F|26|G|27|R|S]|$F|28|G|29|R|S]]|9|@]|A|$]]|$1|T|3|U|5|6|7|2A|8|@$F|2B|G|2C|R|S]|$F|2D|G|2E|R|S]|$F|2F|G|2G|R|S]]|9|@]|A|$]]|$1|V|3|W|5|6|7|2H|8|@$F|2I|G|2J|R|S]]|9|@]|A|$]]|$1|X|3|Y|5|Z|7|2K|8|@]|9|@]|A|$10|11]]|$1|12|3|13|5|6|7|2L|8|@$F|2M|G|2N|R|S]|$F|2O|G|2P|R|S]]|9|@$F|2Q|G|2R|1|2S]]|A|$]]|$1|14|3|15|5|Z|7|2T|8|@]|9|@]|A|$10|11]]|$1|16|3|17|5|6|7|2U|8|@]|9|@]|A|$]]|$1|18|3|19|5|Z|7|2V|8|@]|9|@]|A|$10|11]]|$1|1A|3|-4|5|6|7|2W|8|@]|9|@]|A|$]]]|1B|$1C|$5|1D|1E|1F|A|$1G|1H]]|1I|$5|1D|1E|1F|A|$1G|1J]]|1K|$5|1D|1E|1F|A|$1G|1L]]|1M|$5|1D|1E|1F|A|$1G|1L]]]]

Wasn't satisfied with the answers above, although they were the start.

After piecing together some different sources here: 
<a href="https://stackoverflow.com/questions/4717550/hasflag-not-recognizing-role-assignment">Previous poster in this thread's SO QnA</a> 
<a href="http://www.codeproject.com/Tips/194233/See-if-a-Flags-enum-is-valid?display=Print" rel="nofollow noreferrer">Code Project Enum Flags Check Post</a> 
<a href="http://devlicious.com/blogs/christopher_bennage/archive/2007/09/13/my-new-little-friend-enum-lt-t-gt.aspx" rel="nofollow noreferrer">Great Enum&lt;T&gt; Utility</a>

I created this so let me know what you think. 
Parameters: 
<code>bool checkZero</code>: tells it to allow <code>0</code> as a flag value. By default <code>input = 0</code> returns empty. 
<code>bool checkFlags</code>: tells it to check whether the <code>Enum</code> is decorated w/ the <code>[Flags]</code> attribute. 
PS. I don't have time right now to figure out the <code>checkCombinators = false</code> alg which will force it to ignore any enum values which are combinations of bits.

<pre><code> public static IEnumerable&lt;TEnum&gt; GetFlags&lt;TEnum&gt;(this TEnum input, bool checkZero = false, bool checkFlags = true, bool checkCombinators = true)
 {
 Type enumType = typeof(TEnum);
 if (!enumType.IsEnum)
 yield break;

 ulong setBits = Convert.ToUInt64(input);
 // if no flags are set, return empty
 if (!checkZero &amp;&amp; (0 == setBits))
 yield break;

 // if it's not a flag enum, return empty
 if (checkFlags &amp;&amp; !input.GetType().IsDefined(typeof(FlagsAttribute), false))
 yield break;

 if (checkCombinators)
 {
 // check each enum value mask if it is in input bits
 foreach (TEnum value in Enum&lt;TEnum&gt;.GetValues())
 {
 ulong valMask = Convert.ToUInt64(value);

 if ((setBits &amp; valMask) == valMask)
 yield return value;
 }
 }
 else
 {
 // check each enum value mask if it is in input bits
 foreach (TEnum value in Enum &lt;TEnum&gt;.GetValues())
 {
 ulong valMask = Convert.ToUInt64(value);

 if ((setBits &amp; valMask) == valMask)
 yield return value;
 }
 }

 }
</code></pre>

This makes use of the Helper Class <a href="http://devlicious.com/blogs/christopher_bennage/archive/2007/09/13/my-new-little-friend-enum-lt-t-gt.aspx" rel="nofollow noreferrer">Enum&lt;T&gt; found here</a> that I updated to use <code>yield return</code> for <code>GetValues</code>:

<pre><code>public static class Enum&lt;TEnum&gt;
{
 public static TEnum Parse(string value)
 {
 return (TEnum)Enum.Parse(typeof(TEnum), value);
 }

 public static IEnumerable&lt;TEnum&gt; GetValues() 
 {
 foreach (object value in Enum.GetValues(typeof(TEnum)))
 yield return ((TEnum)value);
 }
} 
</code></pre>

Finally, here's a example of using it:

<pre><code> private List&lt;CountType&gt; GetCountTypes(CountType countTypes)
 {
 List&lt;CountType&gt; cts = new List&lt;CountType&gt;();

 foreach (var ct in countTypes.GetFlags())
 cts.Add(ct);

 return cts;
 }
</code></pre>

blocks|key|1092300|text|基于上面Greg的回答，这也考虑到了枚举中值为0的情况，例如None+=0。在这种情况下，它不应该遍历该值。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092301|public+static+IEnumerable<Enum>+ToEnumerable(this+Enum+input)
{
++++foreach+(Enum+value+in+Enum.GetValues(input.GetType()))
++++++++if+(input.HasFlag(value)+&&+Convert.ToInt64(value)+!=+0)
++++++++++++yield+return+value;
}|code-block|syntax|javascript|1092302|有谁知道如何进一步改进这一点，以便它能够处理枚举中的所有标志都以一种超级智能的方式设置的情况，可以处理所有基础枚举类型以及all+=+~0和all+=+EnumValue1+%7C+EnumValue2+%7C+EnumValue3+%7C+...|1092303|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Building upon Greg's answer above, this also takes care of the case where you have a value 0 in your enum, such as None = 0. In which case, it should not iterate over that value.

<pre><code>public static IEnumerable&lt;Enum&gt; ToEnumerable(this Enum input)
{
 foreach (Enum value in Enum.GetValues(input.GetType()))
 if (input.HasFlag(value) &amp;&amp; Convert.ToInt64(value) != 0)
 yield return value;
}
</code></pre>

Would anyone know how to improve upon this even further so that it can handle the case where all flags in the enum are set in a super smart way that could handle all underlying enum type and the case of All = ~0 and All = EnumValue1 | EnumValue2 | EnumValue3 | ...

blocks|key|877454|text|您可以使用枚举中的迭代器。从MSDN代码开始：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|877455|public+class+DaysOfTheWeek+:+System.Collections.IEnumerable
{
++++int[]+dayflag+=+{+1,+2,+4,+8,+16,+32,+64+};
++++string[]+days+=+{+"Mon",+"Tue",+"Wed",+"Thu",+"Fri",+"Sat",+"Sun"+};
++++public+string+value+{+get;+set;+}

++++public+System.Collections.IEnumerator+GetEnumerator()
++++{
++++++++for+(int+i+=+0;+i+<+days.Length;+i%2B%2B)
++++++++{
++++++++++++if+value+>>+i+&+1+==+dayflag[i]+{
++++++++++++++++yield+return+days[i];
++++++++++++}
++++++++}
++++}
}|code-block|syntax|javascript|877456|它没有经过测试，所以如果我犯了一个错误，请随时给我打电话。(显然，它不是可重入的。)您必须预先赋值，或者将其分解到另一个使用enum.dayflag和enum.days的函数中。你也许可以带着提纲走到某个地方。|877457|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

You can use an Iterator from the Enum. Starting from the MSDN code:

<pre><code>public class DaysOfTheWeek : System.Collections.IEnumerable
{
 int[] dayflag = { 1, 2, 4, 8, 16, 32, 64 };
 string[] days = { "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun" };
 public string value { get; set; }

 public System.Collections.IEnumerator GetEnumerator()
 {
 for (int i = 0; i &lt; days.Length; i++)
 {
 if value &gt;&gt; i &amp; 1 == dayflag[i] {
 yield return days[i];
 }
 }
 }
}
</code></pre>

It's not tested, so if I made a mistake feel free to call me out. (obviously it's not re-entrant.) You'd have to assign value beforehand, or break it out into another function that uses enum.dayflag and enum.days. You might be able to go somewhere with the outline.

blocks|key|1092838|text|这是另一个使用Linq的C#+7.3解决方案|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092839|public+static+class+FlagEnumExtensions
{
++++public+static+IEnumerable<T>+GetFlags<T>(this+T+en)+where+T+:+struct,+Enum
++++{
++++++++return+Enum.GetValues<T>().Where(member+=>+en.HasFlag(member));
++++}
}|code-block|syntax|javascript|1092840|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Here's yet another C# 7.3 solution using Linq
<pre><code>public static class FlagEnumExtensions
{
 public static IEnumerable&lt;T&gt; GetFlags&lt;T&gt;(this T en) where T : struct, Enum
 {
 return Enum.GetValues&lt;T&gt;().Where(member =&gt; en.HasFlag(member));
 }
}
</code></pre>

blocks|key|1092513|text|它可以是下面的代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092514|public+static+string+GetEnumString(MyEnum+inEnumValue)
{
++++StringBuilder+sb+=+new+StringBuilder();

++++foreach+(MyEnum+e+in+Enum.GetValues(typeof(MyEnum+)))
++++{
++++++++if+((e+&+inEnumValue)+!=+0)
++++++++{
+++++++++++sb.Append(e.ToString());
+++++++++++sb.Append(",+");
++++++++}
++++}

+++return+sb.ToString().Trim().TrimEnd(',');
}|code-block|syntax|javascript|1092515|仅当枚举值包含在值中时，它才进入内部|1092516|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

It could be aswell as the following code:

<pre><code>public static string GetEnumString(MyEnum inEnumValue)
{
 StringBuilder sb = new StringBuilder();

 foreach (MyEnum e in Enum.GetValues(typeof(MyEnum )))
 {
 if ((e &amp; inEnumValue) != 0)
 {
 sb.Append(e.ToString());
 sb.Append(", ");
 }
 }

 return sb.ToString().Trim().TrimEnd(',');
}
</code></pre>

It goes inside if only when the enum value is contained on the value

blocks|key|878028|text|所有的答案都适用于简单的标志，当组合标志时，你可能会遇到问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|878029|[Flags]
enum+Food
{
++None=0
++Bread=1,
++Pasta=2,
++Apples=4,
++Banana=8,
++WithGluten=Bread%7CPasta,
++Fruits+=+Apples+%7C+Banana,
}|code-block|syntax|javascript|878030|可能需要添加一个检查来测试枚举值本身是否是一个组合。你可能需要像Henk+van+Boeijen在这里发布的东西来满足你的需求(你需要向下滚动一点)|offset|length|878031|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/1339976/how-to-check-if-any-flags-of-a-flag-combination-are-set^0|0|0|W|G|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

All the answers work well with simple flags, you're probably going to get into issues when flags are combined. 

<pre><code>[Flags]
enum Food
{
 None=0
 Bread=1,
 Pasta=2,
 Apples=4,
 Banana=8,
 WithGluten=Bread|Pasta,
 Fruits = Apples | Banana,
}
</code></pre>

probably need to add a check to test if the enum value it self is a combination. 
You'd probably need something like posted here by <a href="https://stackoverflow.com/questions/1339976/how-to-check-if-any-flags-of-a-flag-combination-are-set">Henk van Boeijen</a> 
to cover your requirement (you need to scroll down a bit)

blocks|key|878150|text|当谈到性能时，这在游戏开发中很重要，所有的解决方案都很糟糕，因为垃圾分配和速度慢。这是一个没有垃圾的解决方案，比公认的答案快100倍以上。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|878151|[Flags]
public+enum+PersonalTraits+:+short
{
++++None+=+1+<<+0,
++++Strength+=+1+<<+1,
++++Agility+=+1+<<+2,
++++Attack+=+1+<<+3,
++++Defence+=+1+<<+4,
++++Vitality+=+1+<<+5,
++++Stamina+=+1+<<+6,
++++Accuracy+=+1+<<+7,
++++Perception+=+1+<<+8,
++++Charisma+=+1+<<+9,
}
PersonalTraits+athlete+=+PersonalTraits.Stamina+%7C+PersonalTraits.Strength;

for+(short+i+=+0,+value+=+0;+value+<=+(short)PersonalTraits.Charisma;+i%2B%2B,+value+=+(short)(1+<<+i))
++++if+(((short)athlete+&+value)+!=+0)
+++++++yield+return+(PersonalTraits)value;|code-block|syntax|javascript|878152|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

When it comes to performance, which is important in game development, all solutions given are terrible because of garbage allocation and slow speed. This is a garbage free, over 100 times faster solution than accepted answer.
<pre><code>[Flags]
public enum PersonalTraits : short
{
 None = 1 &lt;&lt; 0,
 Strength = 1 &lt;&lt; 1,
 Agility = 1 &lt;&lt; 2,
 Attack = 1 &lt;&lt; 3,
 Defence = 1 &lt;&lt; 4,
 Vitality = 1 &lt;&lt; 5,
 Stamina = 1 &lt;&lt; 6,
 Accuracy = 1 &lt;&lt; 7,
 Perception = 1 &lt;&lt; 8,
 Charisma = 1 &lt;&lt; 9,
}
PersonalTraits athlete = PersonalTraits.Stamina | PersonalTraits.Strength;

for (short i = 0, value = 0; value &lt;= (short)PersonalTraits.Charisma; i++, value = (short)(1 &lt;&lt; i))
 if (((short)athlete &amp; value) != 0)
 yield return (PersonalTraits)value;
</code></pre>

blocks|key|1092457|text|您可以通过转换为int直接执行此操作，但这样会放松类型检查。我认为最好的方法是使用类似于我的建议的东西。它始终保持正确的类型。不需要转换。它并不完美，因为装箱会在性能上增加一些打击。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1092458|不是完美的(拳击)，但它在没有警告的情况下完成了工作...|1092459|///+<summary>
///+Return+an+enumerators+of+input+flag(s)
///+</summary>
///+<param+name="input"></param>
///+<returns></returns>
public+static+IEnumerable<T>+GetFlags<T>(this+T+input)
{
++++foreach+(Enum+value+in+Enum.GetValues(input.GetType()))
++++{
++++++++if+((int)+(object)+value+!=+0)+//+Just+in+case+somebody+has+defined+an+enum+with+0.
++++++++{
++++++++++++if+(((Enum)+(object)+input).HasFlag(value))
++++++++++++++++yield+return+(T)+(object)+value;
++++++++}
++++}
}|code-block|syntax|javascript|1092460|用法：|1092461|++++FileAttributes+att+=+FileAttributes.Normal+%7C+FileAttributes.Compressed;
++++foreach+(FileAttributes+fa+in+att.GetFlags())
++++{
++++++++...
++++}|1092462|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

You can do it directly by converting to int but you will loose type checking. 
I think the best way is use something similar to my proposition. It keep the proper type all the way. No conversion required. It is not perfect due to boxing which will add a little hit in performance.

Not perfect (boxing), but it does the job with no warning...

<pre><code>/// &lt;summary&gt;
/// Return an enumerators of input flag(s)
/// &lt;/summary&gt;
/// &lt;param name="input"&gt;&lt;/param&gt;
/// &lt;returns&gt;&lt;/returns&gt;
public static IEnumerable&lt;T&gt; GetFlags&lt;T&gt;(this T input)
{
 foreach (Enum value in Enum.GetValues(input.GetType()))
 {
 if ((int) (object) value != 0) // Just in case somebody has defined an enum with 0.
 {
 if (((Enum) (object) input).HasFlag(value))
 yield return (T) (object) value;
 }
 }
}
</code></pre>

Usage:

<pre><code> FileAttributes att = FileAttributes.Normal | FileAttributes.Compressed;
 foreach (FileAttributes fa in att.GetFlags())
 {
 ...
 }
</code></pre>

If I have a variable holding a flags enum, can I somehow iterate over the single-bit values in that specific variable? Or do I have to use Enum.GetValues to iterate over the entire enum and check which ones are set?

How to iterate over values of an Enum having flags?

游戏开发

如果我有一个包含标志枚举的变量，我可以以某种方式迭代该特定变量中的单位值吗？或者，我是否必须使用Enum.GetValues遍历整个枚举并检查设置了哪些枚举？

问如何迭代具有标志的枚举的值？
EN

回答 16

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问如何迭代具有标志的枚举的值？EN

回答 16

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问如何迭代具有标志的枚举的值？
EN