我有一门课叫问题（复数）。在这个类中有一个名为Question（单数）的枚举，看起来像这样。
public enum Question
{
Role = 2,
ProjectFunding = 3,
TotalEmployee = 4,
NumberOfServers = 5,
TopBusinessConcern = 6
}
在Questions类中，我有一个get（intfoo）函数，它为该foo返回Questions对象。有没有一种简单的方法可以从枚举中获取整数值，这样我就可以执行类似于Questions.get（Questions.Role）的操作？
当前回答
public enum Suit : int
{
Spades = 0,
Hearts = 1,
Clubs = 2,
Diamonds = 3
}
Console.WriteLine((int)(Suit)Enum.Parse(typeof(Suit), "Clubs"));
// From int
Console.WriteLine((Suit)1);
// From a number you can also
Console.WriteLine((Suit)Enum.ToObject(typeof(Suit), 1));
if (typeof(Suit).IsEnumDefined("Spades"))
{
var res = (int)(Suit)Enum.Parse(typeof(Suit), "Spades");
Console.Out.WriteLine("{0}", res);
}
其他回答
Use:
Question question = Question.Role;
int value = question.GetHashCode();
这将导致值==2。
只有当枚举适合于int时，这才是真的。
您可以通过对定义的枚举类型实现一个扩展方法来做到这一点：
public static class MyExtensions
{
public static int getNumberValue(this Question questionThis)
{
return (int)questionThis;
}
}
这简化了获取当前枚举值的int值：
Question question = Question.Role;
int value = question.getNumberValue();
or
int value = Question.Role.getNumberValue();
为了确保枚举值存在，然后解析它，还可以执行以下操作。
// Fake Day of Week
string strDOWFake = "SuperDay";
// Real Day of Week
string strDOWReal = "Friday";
// Will hold which ever is the real DOW.
DayOfWeek enmDOW;
// See if fake DOW is defined in the DayOfWeek enumeration.
if (Enum.IsDefined(typeof(DayOfWeek), strDOWFake))
{
// This will never be reached since "SuperDay"
// doesn't exist in the DayOfWeek enumeration.
enmDOW = (DayOfWeek)Enum.Parse(typeof(DayOfWeek), strDOWFake);
}
// See if real DOW is defined in the DayOfWeek enumeration.
else if (Enum.IsDefined(typeof(DayOfWeek), strDOWReal))
{
// This will parse the string into it's corresponding DOW enum object.
enmDOW = (DayOfWeek)Enum.Parse(typeof(DayOfWeek), strDOWReal);
}
// Can now use the DOW enum object.
Console.Write("Today is " + enmDOW.ToString() + ".");
我能想到的最简单的解决方案是重载Get（int）方法，如下所示：
[modifiers] Questions Get(Question q)
{
return Get((int)q);
}
其中[modifiers]通常可以与Get（int）方法相同。如果无法编辑Questions类或出于某种原因不想编辑，可以通过编写扩展来重载该方法：
public static class Extensions
{
public static Questions Get(this Questions qs, Question q)
{
return qs.Get((int)q);
}
}
在Visual Basic中，它应该是：
Public Enum Question
Role = 2
ProjectFunding = 3
TotalEmployee = 4
NumberOfServers = 5
TopBusinessConcern = 6
End Enum
Private value As Integer = CInt(Question.Role)
