How to get C# Enum description from value?

Possible Duplicate:
Getting attributes of Enum's value

I have an enum with Description attributes like this:

public enum MyEnum
{
    Name1 = 1,
    [Description("Here is another")]
    HereIsAnother = 2,
    [Description("Last one")]
    LastOne = 3
}

I found this bit of code for retrieving the description based on an Enum

public static string GetEnumDescription(Enum value)
{
    FieldInfo fi = value.GetType().GetField(value.ToString());

    DescriptionAttribute[] attributes =
        (DescriptionAttribute[])fi.GetCustomAttributes(
        typeof(DescriptionAttribute),
        false);

    if (attributes != null &&
        attributes.Length > 0)
        return attributes[0].Description;
    else
        return value.ToString();
}

This allows me to write code like:

var myEnumDescriptions = from MyEnum n in Enum.GetValues(typeof(MyEnum))
                         select new { ID = (int)n, Name = Enumerations.GetEnumDescription(n) };

What I want to do is if I know the enum value (eg 1) - how can I retrieve the description? In other words, how can I convert an integer into an "Enum value" to pass to my GetDescription method?

---

int value = 1;
string description = Enumerations.GetEnumDescription((MyEnum)value);

C＃中enum的默认底层数据类型是int ，您可以将其转换为int 。

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I implemented this in a generic, type-safe way in Unconstrained Melody - you'd use:

string description = Enums.GetDescription((MyEnum)value);

This:

Ensures (with generic type constraints) that the value really is an enum value

Avoids the boxing in your current solution

Caches all the descriptions to avoid using reflection on every call

Has a bunch of other methods, including the ability to parse the value from the description

I realise the core answer was just the cast from an int to MyEnum , but if you're doing a lot of enum work it's worth thinking about using Unconstrained Melody :)

---

I put the code together from the accepted answer in a generic extension method, so it could be used for all kinds of objects:

public static string DescriptionAttr<T>(this T source)
{
    FieldInfo fi = source.GetType().GetField(source.ToString());

    DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(
        typeof(DescriptionAttribute), false);

    if (attributes != null && attributes.Length > 0) return attributes[0].Description;
    else return source.ToString();
}

Using an enum like in the original post, or any other class whose property is decorated with the Description attribute, the code can be consumed like this:

string enumDesc = MyEnum.HereIsAnother.DescriptionAttr();
string classDesc = myInstance.SomeProperty.DescriptionAttr();

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