blocks|key|324662|text|System.Enum不能直接转换为Integer，但它确实显式实现了IConvertible，这意味着您可以使用以下代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|324663|public+void+AddLink(Enum+enumVal)
{
++++string+identifier+=+m_EnumInterpreter(Convert.ToInt32(enumVal));
++++AddLink(identifier);
}|code-block|syntax|javascript|324664|请记住，如果您的Enum实际上使用的不是Integer+(例如浮点数)，那么您将在转换时丢失非整数数据。或者明显地将转换调用替换为您要转换的任何内容(如果已知)|324665|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|$]]

System.Enum cannot be directly cast to Integer, but it does explicitly implement IConvertible, meaning you can use the following:

<pre><code>public void AddLink(Enum enumVal)
{
 string identifier = m_EnumInterpreter(Convert.ToInt32(enumVal));
 AddLink(identifier);
}
</code></pre>

Keep in mind that if your Enum is actually using something other than an Integer (such as a float), you'll lose the non-integer data on conversion. Or obviously replace the Convert call with whatever you are converting from (if it's known)

blocks|key|324656|text|不，您不能将其转换为整数，因为System.Enum不是枚举，它只是枚举的基类。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|324657|编辑：|324658|您可以按如下方式获得值，但它很难看：|324659|int+intVar+=+(int)enuYourEnum.GetType().GetField("value__").GetValue(objYourEnum);|code-block|syntax|javascript|324660|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|O|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|P|8|@]|9|@]|A|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

No, you aren't able to cast it to an int because System.Enum is not an enum, it's just the base class for enums.

EDIT:

You can get the value as follows, but it is ugly:

<pre><code>int intVar = (int)enuYourEnum.GetType().GetField("value__").GetValue(objYourEnum);
</code></pre>

blocks|key|3294946|text|试试这个..。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3294947|m_EnumInterpreter((int)+(object)+enumVal)；|3294948|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

try this..

m_EnumInterpreter((int) (object) enumVal);

blocks|key|329629|text|这里有各种各样的东西：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|329630|1)+Ryan的回答看起来不错，但是...我宁愿将枚举向下传递给枚举解释器，这样您就可以完成整个Convert.To...那里。如果您知道您只使用基于整数的枚举，那么Convert.ToInt32()就可以了。否则，您可能希望通过使用反射或尝试/捕获其他转换来添加。|329631|2)您还可以考虑使用枚举类的成员，如.GetName()、.GetValue()等，因为它们直接处理独立于枚举类型的已定义名称和值。|329632|3)从技术上讲，我不会在枚举解释器之外抛出异常。如果该条件通常为真，则从枚举解释器内部抛出异常，以便类的所有使用都将受益于验证。否则，您可能最终会复制代码。|329633|4)从你的变量命名来看，你似乎有C%2B%2B/MFC背景。您可能想要了解C#风格的命名约定，它将使您在使用/阅读他人的代码和库时轻松自如。请查看MS的StyleCop，以获得帮助命名的好插件。|329634|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|N|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|O|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|P|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|K|$]]

Various things here:

1) the answer of Ryan looks ok, but... I would rather pass the Enum down to the enum interpreter, so that you can do the whole Convert.To... there. If you know that you are using ONLY integer based enums, the Convert.ToInt32() is just fine. Otherwise you may want to add by using either reflection or try/catch other conversions.

2) You may also consider using members of the Enum class, like .GetName(), .GetValue(), etc. since they deal directly with the defined names and values independent of the enum type.

3) technically I would not throw the exception outside the enum interpreter. If that condition is generally true, throw the exception from inside the enum interpreter, so that all uses of the class will benefit of the validation. Or you might end up duplicating code.

4) you seem to have an C++/MFC background judging from your variable naming. You might want to get into C# style naming conventions, it will ease your life when using/reading other peoples code and libraries. Check out MS's StyleCop for a good addin to help with naming.

blocks|key|326334|text|我不知道是否应该在我的问题中包括这一点，或者作为一个答案。问题是，这不是答案，但它是对我有效的答案。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|326335|我在尝试其他东西时偶然发现，如果我只是把它放在字符串的末尾，我就会得到我想要的东西：|326336|throw+new+Exception("EnumInterpreter+returns+empty+string+for+enumVal="+%2B+enumVal);
//EnumInterpreter+returns+empty+string+for+enumVal=3720116125|code-block|syntax|javascript|326337|在我的问题中，我实际上简化为int，真实的数据类型是uint+(在这个特定的例子中)。幸运的是，由于我实际上只需要字符串，所以我不必担心这一点。|326338|我不确定其他三个答案中哪一个是“正确的”，所以投票吧……|326339|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]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

I don't know whether to include this in my question, or as an answer. The problem is that it isn't THE answer, but it is the answer that works for me.

What I discovered, by chance while trying something else, is that if I just wodge it onto the end of a string, I get what I want:

<pre><code>throw new Exception("EnumInterpreter returns empty string for enumVal=" + enumVal);
//EnumInterpreter returns empty string for enumVal=3720116125
</code></pre>

I actually simplified to int in my question, the real data type is uint (in this particular instance). Fortunately, given that I only actually wanted the string, I don't have to worry about that.

I'm not sure which of the three other answers is 'right', so vote away...

blocks|key|3081703|text|我知道这可能不是你确切的问题的解决方案，但我只是想发布我是如何为我正在使用的特定API解决这个问题的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3081704|int+result+=+(int)+(ActualEnumType)+MethodThatReturnsSystemEnumType(+arg1,+arg2+);|code-block|syntax|javascript|3081705|希望这能对某些人有所帮助。双播FTW。|3081706|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|$]]

I understand that this is probably not the solution to your exact problem, but I just want to post how I solved this for a particular API I was using.

<pre><code>int result = (int) (ActualEnumType) MethodThatReturnsSystemEnumType( arg1, arg2 );
</code></pre>

Hopefully that will be of help to someone. Double cast FTW.

blocks|key|3294938|text|为什么不将枚举解析为一个字符串并返回实际的枚举值呢？|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3294939|public+enum+MyEnum+{+Flower+=+1,+Tree+=+2,+Animal+=+3+};

string+name+=+MyEnum.Flower.ToString();+//+returns+"Flower"|code-block|syntax|javascript|3294940|我认为.ToString()已经被弃用了，我不确定是否有新的方式去做。我本以为实际的枚举表示会比int更有用？|offset|length|style|CODE|3294941|entityMap^0|0|0|3|B|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Why not parse the enum to a string and return the actual enum value?

<pre><code>public enum MyEnum { Flower = 1, Tree = 2, Animal = 3 };

string name = MyEnum.Flower.ToString(); // returns "Flower"
</code></pre>

I think <code>.ToString()</code> is deprecated and I'm not sure about the new way to do it. I would've thought the actual enum representation would be more useful than the int?

(OK, I'll expose the depths of my ignorance here, please be gentle)

Background

I've got a method which looks (a bit) like this:

<pre><code>public void AddLink(Enum enumVal)
{
 string identifier = m_EnumInterpreter(enumVal);
 AddLink(identifier);
}
</code></pre>

The EnumInterpreter is a Func&lt;Enum, string> that is passed in when the parent class is created.

I'm using Enum because at this level it is 'none of my business'- I don't care which specific enum it is. The calling code just uses a (generated) enum to avoid magic strings.

Question

If the EnumInterpreter sends back an empty string, I'd like to throw an exception with the actual value of enumVal. I thought I would just be able to cast to int, but it the compiler won't have it. What am I doing wrong? (Please don't say 'everything').

Cannot convert type 'System.Enum' to int

编译器

解释器

(好的，我在这里暴露我的无知之深，请温文点)背景我有一个方法，看起来(有点)像这样：public void AddLink(Enum enumVal){ string identifier = m_EnumInterpreter(enumVal); AddLink(identifier);}EnumInterpreter是一个在创建父类时传入的Func<Enum、string>。我

问无法将类型“System.Enum”转换为int
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