如何在C#中枚举枚举?

例如,以下代码无法编译:

public enum Suit
{
    Spades,
    Hearts,
    Clubs,
    Diamonds
}

public void EnumerateAllSuitsDemoMethod()
{
    foreach (Suit suit in Suit)
    {
        DoSomething(suit);
    }
}

它给出了以下编译时错误:

“Suit”是“type”,但与“variable”类似

它在第二个Suit关键字上失败。


当前回答

如果您有:

enum Suit
{
   Spades,
   Hearts,
   Clubs,
   Diamonds
}

这:

foreach (var e in Enum.GetValues(typeof(Suit)))
{
    Console.WriteLine(e.ToString() + " = " + (int)e);
}

将输出:

Spades = 0
Hearts = 1
Clubs = 2
Diamonds = 3

其他回答

我想这对你有帮助。

public class Program
{

    public static List<T> GetEnamList<T>()
    {
        var enums = Enum.GetValues(typeof(T)).Cast<T>().Select(v => v).ToList();
        return enums;
    }
    private void LoadEnumList()
    {
        List<DayofWeek> dayofweeks = GetEnamList<DayofWeek>();

        foreach (var item in dayofweeks)
        {
            dayofweeks.Add(item);
        }
    }
}

    public enum DayofWeek
    {
        Monday,
        Tuesday,
        Wensday,
        Thursday,
        Friday,
        Sturday,
        Sunday
    }

我使用ToString(),然后拆分并解析flags中的spit数组。

[Flags]
public enum ABC {
   a = 1,
   b = 2,
   c = 4
};

public IEnumerable<ABC> Getselected (ABC flags)
{
   var values = flags.ToString().Split(',');
   var enums = values.Select(x => (ABC)Enum.Parse(typeof(ABC), x.Trim()));
   return enums;
}

ABC temp= ABC.a | ABC.b;
var list = getSelected (temp);
foreach (var item in list)
{
   Console.WriteLine(item.ToString() + " ID=" + (int)item);
}

当你有这样的枚举时

enum DemoFlags
{
    DemoFlag = 1,
    OtherFlag = 2,
    TestFlag = 4,
    LastFlag = 8,
}

有了这个任务

DemoFlags demoFlags = DemoFlags.DemoFlag | DemoFlags.TestFlag;

需要这样的结果

"DemoFlag | TestFlag"

此方法有助于:

public static string ConvertToEnumString<T>(T enumToConvert, string separator = " | ") where T : Enum
{
    StringBuilder convertedEnums = new StringBuilder();

    foreach (T enumValue in Enum.GetValues(typeof(T)))
    {
        if (enumToConvert.HasFlag(enumValue)) convertedEnums.Append($"{ enumValue }{separator}");
    }

    if (convertedEnums.Length > 0) convertedEnums.Length -= separator.Length;

    return convertedEnums.ToString();
}

通过组合最重要的答案,我总结了一个非常简单的扩展:

public static class EnumExtensions
{
    /// <summary>
    /// Gets all items for an enum value.
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="value">The value.</param>
    /// <returns></returns>
    public static IEnumerable<T> GetAllItems<T>(this T value) where T : Enum
    {
        return (T[])Enum.GetValues(typeof (T));
    }
}

它干净、简单,而且,根据@Jeppe Stig Nielsen的评论,速度很快。

public void PrintAllSuits()
{
    foreach(string suit in Enum.GetNames(typeof(Suits)))
    {
        Console.WriteLine(suit);
    }
}