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Enforcing static class constants as a data type

I have a static class with constants. I am looking for options to create a method which takes a dictionary as an argument and enforcing the key to be one of the constants from the static class.Here is my static class with constants.
Here is what I am trying to do
And here is what I am trying to enforce

From the sound of it, an Enum would be more suited to what you're trying to do.
public enum MyConstants
{
FirstName,
LastName,
Title
}
public void CreateMe(Dictionary<MyConstants, string> propertyBag)
{
...
}
UPDATED
You could combine this with attributes to associate each enum with a specific string like so:
public enum PropertyNames
{
[Description("first_name")]
FirstName,
[Description("last_name")]
LastName,
[Description("title")]
Title
}
The value of each description attribute associated with each enum value could easily be grabbed via an extension method, like so:
public static class EnumExtensions
{
public static string GetDescription(this Enum value)
{
FieldInfo fieldInfo = value.GetType().GetField(value.ToString());
DescriptionAttribute[] attributes =
(DescriptionAttribute[])fieldInfo.GetCustomAttributes(
typeof(DescriptionAttribute),
false);
if (attributes != null &&
attributes.Length > 0)
return attributes[0].Description;
else
return value.ToString();
}
}
Then in your "CreateMe"-method you can get the description and value of each dictionary entry by doing something similar to this:
void CreateMe(Dictionary<PropertyNames, string> propertyBag)
{
foreach (var propertyPair in propertyBag)
{
string propertyName = propertyPair.Key.GetDescription();
string propertyValue = propertyPair.Value;
}
}

Even though this has been already answered, there is another approach, like so:
public class MyOwnEnum
{
public string Value { get; private set; }
private MyOwnEnum(string value)
{
Value = value;
}
public static readonly MyOwnEnum FirstName = new MyOwnEnum("Firstname");
public static readonly MyOwnEnum LastName = new MyOwnEnum("LastName");
}
It behaves same way like Enum and can be used in your code with same syntax. I cannot give credit to whoever came up with it, but I believe I came upon it when searching for Enums with multiple values.

With strings you can't enforce fact that keys come from limited set of vialues compile time.
Use enum or custom class (possibly with implicit conversion to string) instead.

Parse StringValueAttribute to return Enum

I currently have a windows phone 8.1 runtime project with enums that use a string value attribute. I want to be able to get an enum value by using the string value attribute, for example use "world" to get the enum value of summer. I am using Windows phone 8.1 runtime so most methods that I have found do not work.
Thanks in advance.
public enum test
{
[StringValue("hello")]
school,
[StringValue("world")]
summer,
[StringValue("fall")]
car
}
public class StringValueAttribute : Attribute
{
private string _value;
public StringValueAttribute(string value)
{
_value = value;
}
public string Value
{
get { return _value; }
}
}

To get to your Attributes you will need to use a method/extension. Folowing this question and answer you can make such a thing:
public class StringValueAttribute : Attribute
{
private string _value;
public StringValueAttribute(string value)
{
_value = value;
}
public string Value
{
get { return _value; }
}
public static string GetStringValue(Enum value)
{
Type type = value.GetType();
FieldInfo fi = type.GetRuntimeField(value.ToString());
return (fi.GetCustomAttributes(typeof(StringValueAttribute), false).FirstOrDefault() as StringValueAttribute).Value;
}
}
Then using this line of code:
string stringTest = StringValueAttribute.GetStringValue(test.summer);
will give a result of "world". (Opposite what you wanted, but hopefuly will give you an idea how to deal with the problem).
Depending on what you want to achieve, you can probably use different methods linke: using Dictionary, struct, properties and probably different ways.
As for parsing Enum values you can achieve it like this:
test testValue = test.summer;
string testString = testValue.ToString();
test EnumValue = (test)Enum.Parse(typeof(test), testString);
EDIT
If you want to get enum from attribute, then this method (probably should be improved) should do the job:
public static T GetFromAttribute<T>(string attributeName)
{
Type type = typeof(T);
return (T)Enum.Parse(typeof(T), type.GetRuntimeFields().FirstOrDefault(
x => (x.CustomAttributes.Count() > 0 && (x.CustomAttributes.FirstOrDefault().ConstructorArguments.FirstOrDefault().Value as string).Equals(attributeName))).Name);
}
Usage:
test EnumTest = StringValueAttribute.GetFromAttribute<test>("world");

Converting a string to a custom enum

I'm trying to set a custom enum property on a custom object by looking at a string value that is held in another object, but I keep getting the error "cannot reference a type through an expression."
so far I've tried
rec.Course = (CourseEnum)Enum.Parse(typeof(CourseEnum), rr.course);
where rec.Course wants a member of the CourseEnum Enumeration, and rr.course is a string.
I also tried to do a switch statement where the value of rr.course is checked (there are only certain values it can be) but get the same result
the enum is defined as follows:
public enum CourseEnum
{
[StringValue("Starters")]
Starters,
[StringValue("Main Course")]
MainCourse,
[StringValue("Desserts")]
Desserts
};
public class StringValue : System.Attribute
{
private string _value;
public StringValue(string value)
{
_value = value;
}
public string Value
{
get { return _value; }
}
}
public static class StringEnum
{
public static string GetStringValue(Enum value)
{
string output = null;
Type type = value.GetType();
//Check first in our cached results...
//Look for our 'StringValueAttribute'
//in the field's custom attributes
FieldInfo fi = type.GetRuntimeField(value.ToString());
StringValue[] attrs =
fi.GetCustomAttributes(typeof(StringValue),
false) as StringValue[];
if (attrs.Length > 0)
{
output = attrs[0].Value;
}
return output;
}
}

I can see in your code that your using Enum.Parse with CourseEnum and it should be recipeCourse I presume.
I can't spot any place in your sample code where4 CourseEnum is defined.

A #Hans Kesting said, the answer was here: Why can not reference a type through an expression?
The problem was using a field that has an enum type with the enum type itself.

How to set string in Enum C#?

I want to create string ENUM in c#.
Basically i wan't to set form name in Enum. When i open form in main page that time i want to switch case for form name and open that particular form.
I know ENUM allows only integer but i want to set it to string.
Any Idea?

Enum cannot be string but you can attach attribute and than you can read the value of enum as below....................
public enum States
{
[Description("New Mexico")]
NewMexico,
[Description("New York")]
NewYork,
[Description("South Carolina")]
SouthCarolina
}
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();
}
here is good article if you want to go through it : Associating Strings with enums in C#

As everyone mentioned, enums can't be strings (or anything else except integers) in C#. I'm guessing you come from Java? It would be nice if .NET had this feature, where enums can be any type.
The way I usually circumvent this is using a static class:
public static class MyValues
{
public static string ValueA { get { return "A"; } }
public static string ValueB { get { return "B"; } }
}
With this technique, you can also use any type. You can call it just like you would use enums:
if (value == MyValues.ValueA)
{
// do something
}

Do this:
private IddFilterCompareToCurrent myEnum =
(IddFilterCompareToCurrent )Enum.Parse(typeof(IddFilterCompareToCurrent[1]),domainUpDown1.SelectedItem.ToString());
[Enum.parse] returns an Object, so you need to cast it.

Im not sure if I understood you corectly but I think you are looking for this?
public enum State { State1, State2, State3 };
public static State CurrentState = State.State1;
if(CurrentState == State.State1)
{
//do something
}

I don't think that enums are the best solution for your problem. As others have already mentionde, the values of an enum can only be integer values.
You could simply use a Dictionary to store the forms along with their name like:
Dictionary<string, Form> formDict = new Dictionary<string, Form>();
private void addFormToDict(Form form) {
formDict[form.Name] = form;
}
// ...
addFormToDict(new MyFirstForm());
addFormToDict(new MySecondForm());
// ... add all forms you want to display to the dictionary
if (formDict.ContainsKey(formName))
formDict[formName].Show();
else
MessageBox.Show(String.Format("Couldn't find form '{0}'", formName));

Either make the names of the Enum members exactly what you want and use .ToString(),
Write a function like this ...
string MyEnumString(MyEnum value)
{
const string MyEnumValue1String = "any string I like 1";
const string MyEnumValue2String = "any string I like 2";
...
switch (value)
{
case MyEnum.Value1:
return MyEnumValue1String;
case MyEnum.Value2:
return MyEnumValue2String;
...
}
}
Or use some dictionary or hash set of values and strings instead.

string enums don't exist in C#. See this related question.
Why don't you use an int (default type for enums) instead of a string?

How to read enum value in ASP.Net?

My enum structure is this
public enum UserRole
{
Administrator = "Administrator",
Simple_User = "Simple User",
Paid_User = "Paid User"
}
Now i want to read this enum value by using its name suppose
String str = UserRole.Simple_User;
it gives me "Simple User" in str instead of "Simple_User"
How we can do this???

You can do a friendly description like so:
public enum UserRole
{
[Description("Total administrator!!1!one")]
Administrator = 1,
[Description("This is a simple user")]
Simple_User = 2,
[Description("This is a paid user")]
Paid_User = 3,
}
And make a helper function:
public static string GetDescription(Enum en)
{
Type type = en.GetType();
MemberInfo[] info = type.GetMember(en.ToString());
if (info != null && info.Length > 0)
{
object[] attrs = info[0].GetCustomAttributes(typeof(DescriptionAttribute), false);
if (attrs != null && attrs.Length > 0)
{
return ((DescriptionAttribute)attrs[0]).Description;
}
}
return en.ToString();
}
And use it like:
string description = GetDescription(UserRole.Administrator);

Okay so by now you know that enum really is a list of numbers that you can give a handy string handle to like:
public enum ErrorCode
{
CTCLSM = 1,
CTSTRPH = 2,
FBR = 3,
SNF = 4
}
Also, as #StriplingWarrior showed, you can go so far by getting the enum string name and replacing underscores etc. But what I think you want is a way of associating a nice human string with each value. How about this?
public enum ErrorCode
{
[EnumDisplayName("Cataclysm")]
CTCLSM = 1,
[EnumDisplayName("Catastrophe")]
CTSTRPH = 2,
[EnumDisplayName("Fubar")]
FBR = 3,
[EnumDisplayName("Snafu")]
SNF = 4
}
Okay there's probably something in System.ComponentModel that does this - let me know. The code for my solution is here:
[AttributeUsage(AttributeTargets.Field)]
public class EnumDisplayNameAttribute : System.Attribute
{
public string DisplayName { get; set; }
public EnumDisplayNameAttribute(string displayName)
{
DisplayName = displayName;
}
}
And the funky Enum extension that makes it possible:
public static string PrettyFormat(this Enum enumValue)
{
string text = enumValue.ToString();
EnumDisplayNameAttribute displayName = (EnumDisplayNameAttribute)enumValue.GetType().GetField(text).GetCustomAttributes(typeof(EnumDisplayNameAttribute), false).SingleOrDefault();
if (displayName != null)
text = displayName.DisplayName;
else
text = text.PrettySpace().Capitalize(true);
return text;
}
So to get the human-friendly value out you could just do ErrorCode.CTSTRPH.PrettyFormat()

Hmm, enums can't have string values. From MSDN's Enum page:
An enumeration is a set of named constants whose underlying type is any integral type except Char.
To get the string version of the enum use the Enum's ToString method.
String str = UserRole.Simple_User.ToString("F");

I'm a little confused by your question, because C# doesn't allow you to declare enums backed by strings. Do you mean that you want to get "Simple User", but you're getting "Simple_User" instead?
How about:
var str = UserRole.Simple_User.ToString().Replace("_", " ");

You can do this by attribute, but really I think using an enum like this is possibly the wrong way to go about things.
I would create a user role interface that exposes a display name property, then implement that interface with a new class for each role, this also let's you add more behaviour in the future.
Or you could use an abstract class so any generic behaviour doesn't get duplicated...