Myujth

Since Enums can be any integral type (byte, int, short, etc.), a more robust way to get the underlying integral value of the enum would be to make use of the GetTypeCode method in conjunction with the Convert class:

enum Sides 
 Left, Right, Top, Bottom

Sides side = Sides.Bottom;

object val = Convert.ChangeType(side, side.GetTypeCode());
Console.WriteLine(val);

This should work regardless of the underlying integral type.

Declare it as a static class having public constants:

public static class Question

 public const int Role = 2;
 public const int ProjectFunding = 3;
 public const int TotalEmployee = 4;
 public const int NumberOfServers = 5;
 public const int TopBusinessConcern = 6;

And then you can reference it as Question.Role, and it always evaluates to an int or whatever you define it as.

Question question = Question.Role;
int value = (int) question;

Will result in value == 2.

On a related note, if you want to get the int value from System.Enum, then given e here:

Enum e = Question.Role;

You can use:

int i = Convert.ToInt32(e);
int i = (int)(object)e;
int i = (int)Enum.Parse(e.GetType(), e.ToString());
int i = (int)Enum.ToObject(e.GetType(), e);

The last two are plain ugly. I prefer the first one.

It's easier than you think - an enum is already an int. It just needs to be reminded:

int y = (int)Question.Role;
Console.WriteLine(y); // prints 2

Example:

public Enum EmpNo

 Raj = 1,
 Rahul,
 Priyanka

And in the code behind to get enum value:

int setempNo = (int)EmpNo.Raj; //This will give setempNo = 1

or

int setempNo = (int)EmpNo.Rahul; //This will give setempNo = 2

Enums will increment by 1, and you can set the start value. If you don't set the start value it will be assigned as 0 initially.

I have recently converted away from using enums in my code in favour of instead using classes with protected constructors and predefined static instances (thanks to Roelof - C# Ensure Valid Enum Values - Futureproof Method).

In light of that, below's how I'd now approach this issue (including implicit conversion to/from int).

public class Question

 // Attributes
 protected int index;
 protected string name;
 // Go with a dictionary to enforce unique index
 //protected static readonly ICollection<Question> values = new Collection<Question>();
 protected static readonly IDictionary<int,Question> values = new Dictionary<int,Question>();

 // Define the "enum" values
 public static readonly Question Role = new Question(2,"Role");
 public static readonly Question ProjectFunding = new Question(3, "Project Funding");
 public static readonly Question TotalEmployee = new Question(4, "Total Employee");
 public static readonly Question NumberOfServers = new Question(5, "Number of Servers");
 public static readonly Question TopBusinessConcern = new Question(6, "Top Business Concern");

 // Constructors
 protected Question(int index, string name)
 
 this.index = index;
 this.name = name;
 values.Add(index, this);
 

 // Easy int conversion
 public static implicit operator int(Question question) =>
 question.index; //nb: if question is null this will return a null pointer exception

 public static implicit operator Question(int index) => 
 values.TryGetValue(index, out var question) ? question : null;

 // Easy string conversion (also update ToString for the same effect)
 public override string ToString() =>
 this.name;

 public static implicit operator string(Question question) =>
 question?.ToString();

 public static implicit operator Question(string name) =>
 name == null ? null : values.Values.FirstOrDefault(item => name.Equals(item.name, StringComparison.CurrentCultureIgnoreCase));


 // If you specifically want a Get(int x) function (though not required given the implicit converstion)
 public Question Get(int foo) =>
 foo; //(implicit conversion will take care of the conversion for you)

The advantage of this approach is you get everything you would have from the enum, but your code's now much more flexible, so should you need to perform different actions based on the value of Question, you can put logic into Question itself (i.e. in the preferred OO fashion) as opposed to putting lots of case statements throughout your code to tackle each scenario.

NB: Answer updated 2018-04-27 to make use of C# 6 features; i.e. declaration expressions and lambda expression body definitions. See revision history for original code. This has the benefit of making the definition a little less verbose; which had been one of the main complaints about this answer's approach.

If you want to get an integer for the enum value that is stored in a variable, wich the type would be Question, to use for example in a method, you can simply do this I wrote in this example:

enum Talen

 Engels = 1, Italiaans = 2, Portugees = 3, Nederlands = 4, Duits = 5, Dens = 6


Talen Geselecteerd; 

public void Form1()

 InitializeComponent()
 Geselecteerd = Talen.Nederlands;


// You can use the Enum type as a parameter, so any enumeration from any enumerator can be used as parameter
void VeranderenTitel(Enum e)

 this.Text = Convert.ToInt32(e).ToString();

This will change the window title to 4 because the variable Geselecteerd is Talen.Nederlands. If I change it to Talen.Portugees and call the method again, the text will change to 3.

I had a hard time finding this simple solution on the internet and I couldn't find it, so I was testing something and found this out. Hope this helps. ;)

To ensure an enum value exists and then parse it, you can also do the following.

// 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() + ".");

I hope this helps.

One more way to do it:

Console.WriteLine("Name: 0, Value: 0:D", Question.Role);

Will result in:

Name: Role, Value: 2

Maybe I missed it but has anyone tried a simple generic extension method. This works great for me. You can avoid the type cast in your API this way but ultimately it results in a change type operation. This is a good case for programming Roselyn to have the compiler make a GetValue method for you.

 public static void Main()
 
 int test = MyCSharpWrapperMethod(TestEnum.Test1);

 Debug.Assert(test == 1);
 

 public static int MyCSharpWrapperMethod(TestEnum customFlag)
 
 return MyCPlusPlusMethod(customFlag.GetValue<int>());
 

 public static int MyCPlusPlusMethod(int customFlag)
 
 //Pretend you made a PInvoke or COM+ call to C++ method that require an integer
 return customFlag;
 

 public enum TestEnum
 
 Test1 = 1,
 Test2 = 2,
 Test3 = 3
 
}

public static class EnumExtensions

 public static T GetValue<T>(this Enum enumeration)
 
 T result = default(T);

 try
 
 result = (T)Convert.ChangeType(enumeration, typeof(T));
 
 catch (Exception ex)
 
 Debug.Assert(false);
 Debug.WriteLine(ex);
 

 return result;
 
 

public enum QuestionType

 Role = 2,
 ProjectFunding = 3,
 TotalEmployee = 4,
 NumberOfServers = 5,
 TopBusinessConcern = 6

...is a fine declaration.

You do have to cast the result to int like so:

int Question = (int)QuestionType.Role

Otherwise, the type is still QuestionType.

This level of strictness is the C# way.

One alternative is to use a class declaration instead:

public class QuestionType

 public static int Role = 2,
 public static int ProjectFunding = 3,
 public static int TotalEmployee = 4,
 public static int NumberOfServers = 5,
 public static int TopBusinessConcern = 6

It's less elegant to declare, but you don't need to cast it in code:

int Question = QuestionType.Role

Alternatively, you may feel more comfortable with Visual Basic, which caters for this type of expectation in many areas.

int number = Question.Role.GetHashCode();

number should have the value 2.

You can do this by implementing an Extension Method to your defined enum type:

public static class MyExtensions

 public static int getNumberValue(this Question questionThis)
 
 return (int)questionThis;
 

This simplify getting int value of current enum value:

Question question = Question.Role;
int value = question.getNumberValue();

or

int value = Question.Role.getNumberValue();

How about a extension method instead:

public static class ExtensionMethods

 public static int IntValue(this Enum argEnum)
 
 return Convert.ToInt32(argEnum);
 

And the usage is slightly prettier:

var intValue = Question.Role.IntValue();

My fav hack with int or smaller enums:

GetHashCode();

For a enum

public enum Test

 Min = Int32.MinValue,
 One = 1,
 Max = Int32.MaxValue,

this

var values = Enum.GetValues(typeof(Test));

foreach (var val in values) 

 Console.WriteLine(val.GetHashCode());
 Console.WriteLine(((int)val));
 Console.WriteLine(val);

outputs

one
1
1 
max
2147483647
2147483647 
min
-2147483648
-2147483648 

Disclaimer:
Doesn't work for enums based on long

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 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);

Following is the extension method

public static string ToEnumString<TEnum>(this int enumValue)

 var enumString = enumValue.ToString();
 if (Enum.IsDefined(typeof(TEnum), enumValue))
 
 enumString = ((TEnum) Enum.ToObject(typeof (TEnum), enumValue)).ToString();
 
 return enumString;

The example I would like to suggest 'to get 'int' value from enum is,'

public enum Sample
Book =1, Pen=2, Pencil =3

int answer = (int)Sample.Book;

now the answer will be 1.

I hope this might help someone.

Since enums can be declared with multiple primitive types, a generic extension method to cast any enum type can be useful.

enum Box

 HEIGHT,
 WIDTH,
 DEPTH


public static void UseEnum()

 int height = Box.HEIGHT.GetEnumValue<int>();
 int width = Box.WIDTH.GetEnumValue<int>();
 int depth = Box.DEPTH.GetEnumValue<int>();


public static T GetEnumValue<T>(this object e) => (T)e;

The easiest solution I can think of is overloading the Get(int) method like this:

[modifiers] Questions Get(Question q)

 return Get((int)q);

where [modifiers] can generally be same as for Get(int) method. If You can't edit the Questions class or for some reason don't want to, You can overload the method by writing an extension:

public static class Extensions

 public static Questions Get(this Questions qs, Question q)
 
 return qs.Get((int)q);
 

Try this one instead of convert enum to int:

public static class ReturnType

 public static readonly int Success = 1;
 public static readonly int Duplicate = 2;
 public static readonly int Error = -1; 

In Vb. It should be

Public Enum Question
 Role = 2
 ProjectFunding = 3
 TotalEmployee = 4
 NumberOfServers = 5
 TopBusinessConcern = 6
End Enum

Private value As Integer = CInt(Question.Role)

I a bit late to the game but I came up with this extension method that includes current language features. By using dynamic, I don't need to make this a generic method and specify the type which keeps the invocation simpler and consistent. Please let me know if I've done something wrong:

public static class EnumEx
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