I have the following code:
// Obtain the string names of all the elements within myEnum
String[] names = Enum.GetNames( typeof( myEnum ) );
// Obtain the values of all the elements within myEnum
Array values = Enum.GetValues( typeof( myEnum ) );
// Print the names and values to file
for ( int i = 0; i < names.Length; i++ )
{
print( names[i], values[i] );
}
However, I cannot index values. Is there an easier way to do this?
Or have I missed something entirely!
This question is related to
c#
enums
iteration
system.array
How about a dictionary list?
Dictionary<string, int> list = new Dictionary<string, int>();
foreach( var item in Enum.GetNames(typeof(MyEnum)) )
{
list.Add(item, (int)Enum.Parse(typeof(MyEnum), item));
}
and of course you can change the dictionary value type to whatever your enum values are.
Old question, but a slightly cleaner approach using LINQ's .Cast<>()
var values = Enum.GetValues(typeof(MyEnum)).Cast<MyEnum>();
foreach(var val in values)
{
Console.WriteLine("Member: {0}",val.ToString());
}
How about a dictionary list?
Dictionary<string, int> list = new Dictionary<string, int>();
foreach( var item in Enum.GetNames(typeof(MyEnum)) )
{
list.Add(item, (int)Enum.Parse(typeof(MyEnum), item));
}
and of course you can change the dictionary value type to whatever your enum values are.
Old question, but a slightly cleaner approach using LINQ's .Cast<>()
var values = Enum.GetValues(typeof(MyEnum)).Cast<MyEnum>();
foreach(var val in values)
{
Console.WriteLine("Member: {0}",val.ToString());
}
You can cast that Array to different types of Arrays:
myEnum[] values = (myEnum[])Enum.GetValues(typeof(myEnum));
or if you want the integer values:
int[] values = (int[])Enum.GetValues(typeof(myEnum));
You can iterate those casted arrays of course :)
How about a dictionary list?
Dictionary<string, int> list = new Dictionary<string, int>();
foreach( var item in Enum.GetNames(typeof(MyEnum)) )
{
list.Add(item, (int)Enum.Parse(typeof(MyEnum), item));
}
and of course you can change the dictionary value type to whatever your enum values are.
You need to cast the array - the returned array is actually of the requested type, i.e. myEnum[] if you ask for typeof(myEnum):
myEnum[] values = (myEnum[]) Enum.GetValues(typeof(myEnum));
Then values[0] etc
You can cast that Array to different types of Arrays:
myEnum[] values = (myEnum[])Enum.GetValues(typeof(myEnum));
or if you want the integer values:
int[] values = (int[])Enum.GetValues(typeof(myEnum));
You can iterate those casted arrays of course :)
Array has a GetValue(Int32) method which you can use to retrieve the value at a specified index.
Ancient question, but 3Dave's answer supplied the easiest approach. I needed a little helper method to generate a Sql script to decode an enum value in the database for debugging. It worked great:
public static string EnumToCheater<T>() {
var sql = "";
foreach (var enumValue in Enum.GetValues(typeof(T)))
sql += $@"when {(int) enumValue} then '{enumValue}' ";
return $@"case ?? {sql}else '??' end,";
}
I have it in a static method, so usage is:
var cheater = MyStaticClass.EnumToCheater<MyEnum>()
Array has a GetValue(Int32) method which you can use to retrieve the value at a specified index.
In the Enum.GetValues results, casting to int produces the numeric value. Using ToString() produces the friendly name. No other calls to Enum.GetName are needed.
public enum MyEnum
{
FirstWord,
SecondWord,
Another = 5
};
// later in some method
StringBuilder sb = new StringBuilder();
foreach (var val in Enum.GetValues(typeof(MyEnum))) {
int numberValue = (int)val;
string friendyName = val.ToString();
sb.Append("Enum number " + numberValue + " has the name " + friendyName + "\n");
}
File.WriteAllText(@"C:\temp\myfile.txt", sb.ToString());
// Produces the output file contents:
/*
Enum number 0 has the name FirstWord
Enum number 1 has the name SecondWord
Enum number 5 has the name Another
*/
Array has a GetValue(Int32) method which you can use to retrieve the value at a specified index.
Here is another. We had a need to provide friendly names for our EnumValues. We used the System.ComponentModel.DescriptionAttribute to show a custom string value for each enum value.
public static class StaticClass
{
public static string GetEnumDescription(Enum currentEnum)
{
string description = String.Empty;
DescriptionAttribute da;
FieldInfo fi = currentEnum.GetType().
GetField(currentEnum.ToString());
da = (DescriptionAttribute)Attribute.GetCustomAttribute(fi,
typeof(DescriptionAttribute));
if (da != null)
description = da.Description;
else
description = currentEnum.ToString();
return description;
}
public static List<string> GetEnumFormattedNames<TEnum>()
{
var enumType = typeof(TEnum);
if (enumType == typeof(Enum))
throw new ArgumentException("typeof(TEnum) == System.Enum", "TEnum");
if (!(enumType.IsEnum))
throw new ArgumentException(String.Format("typeof({0}).IsEnum == false", enumType), "TEnum");
List<string> formattedNames = new List<string>();
var list = Enum.GetValues(enumType).OfType<TEnum>().ToList<TEnum>();
foreach (TEnum item in list)
{
formattedNames.Add(GetEnumDescription(item as Enum));
}
return formattedNames;
}
}
In Use
public enum TestEnum
{
[Description("Something 1")]
Dr = 0,
[Description("Something 2")]
Mr = 1
}
static void Main(string[] args)
{
var vals = StaticClass.GetEnumFormattedNames<TestEnum>();
}
This will end returning "Something 1", "Something 2"
Here is a simple way to iterate through your custom Enum object
For Each enumValue As Integer In [Enum].GetValues(GetType(MyEnum))
Print([Enum].GetName(GetType(MyEnum), enumValue).ToString)
Next
You can cast that Array to different types of Arrays:
myEnum[] values = (myEnum[])Enum.GetValues(typeof(myEnum));
or if you want the integer values:
int[] values = (int[])Enum.GetValues(typeof(myEnum));
You can iterate those casted arrays of course :)
You can simplify this using format strings. I use the following snippet in usage messages:
writer.WriteLine("Exit codes are a combination of the following:");
foreach (ExitCodes value in Enum.GetValues(typeof(ExitCodes)))
{
writer.WriteLine(" {0,4:D}: {0:G}", value);
}
The D format specifier formats the enum value as a decimal. There's also an X specifier that gives hexadecimal output.
The G specifier formats an enum as a string. If the Flags attribute is applied to the enum then combined values are supported as well. There's an F specifier that acts as if Flags is always present.
See Enum.Format().
What about using a foreach loop, maybe you could work with that?
int i = 0;
foreach (var o in values)
{
print(names[i], o);
i++;
}
something like that perhaps?
Another solution, with interesting possibilities:
enum Days { Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday }
static class Helpers
{
public static IEnumerable<Days> AllDays(Days First)
{
if (First == Days.Monday)
{
yield return Days.Monday;
yield return Days.Tuesday;
yield return Days.Wednesday;
yield return Days.Thursday;
yield return Days.Friday;
yield return Days.Saturday;
yield return Days.Sunday;
}
if (First == Days.Saturday)
{
yield return Days.Saturday;
yield return Days.Sunday;
yield return Days.Monday;
yield return Days.Tuesday;
yield return Days.Wednesday;
yield return Days.Thursday;
yield return Days.Friday;
}
}
Array has a GetValue(Int32) method which you can use to retrieve the value at a specified index.
What about using a foreach loop, maybe you could work with that?
int i = 0;
foreach (var o in values)
{
print(names[i], o);
i++;
}
something like that perhaps?
You need to cast the array - the returned array is actually of the requested type, i.e. myEnum[] if you ask for typeof(myEnum):
myEnum[] values = (myEnum[]) Enum.GetValues(typeof(myEnum));
Then values[0] etc
Ancient question, but 3Dave's answer supplied the easiest approach. I needed a little helper method to generate a Sql script to decode an enum value in the database for debugging. It worked great:
public static string EnumToCheater<T>() {
var sql = "";
foreach (var enumValue in Enum.GetValues(typeof(T)))
sql += $@"when {(int) enumValue} then '{enumValue}' ";
return $@"case ?? {sql}else '??' end,";
}
I have it in a static method, so usage is:
var cheater = MyStaticClass.EnumToCheater<MyEnum>()
Here is another. We had a need to provide friendly names for our EnumValues. We used the System.ComponentModel.DescriptionAttribute to show a custom string value for each enum value.
public static class StaticClass
{
public static string GetEnumDescription(Enum currentEnum)
{
string description = String.Empty;
DescriptionAttribute da;
FieldInfo fi = currentEnum.GetType().
GetField(currentEnum.ToString());
da = (DescriptionAttribute)Attribute.GetCustomAttribute(fi,
typeof(DescriptionAttribute));
if (da != null)
description = da.Description;
else
description = currentEnum.ToString();
return description;
}
public static List<string> GetEnumFormattedNames<TEnum>()
{
var enumType = typeof(TEnum);
if (enumType == typeof(Enum))
throw new ArgumentException("typeof(TEnum) == System.Enum", "TEnum");
if (!(enumType.IsEnum))
throw new ArgumentException(String.Format("typeof({0}).IsEnum == false", enumType), "TEnum");
List<string> formattedNames = new List<string>();
var list = Enum.GetValues(enumType).OfType<TEnum>().ToList<TEnum>();
foreach (TEnum item in list)
{
formattedNames.Add(GetEnumDescription(item as Enum));
}
return formattedNames;
}
}
In Use
public enum TestEnum
{
[Description("Something 1")]
Dr = 0,
[Description("Something 2")]
Mr = 1
}
static void Main(string[] args)
{
var vals = StaticClass.GetEnumFormattedNames<TestEnum>();
}
This will end returning "Something 1", "Something 2"
Another solution, with interesting possibilities:
enum Days { Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday }
static class Helpers
{
public static IEnumerable<Days> AllDays(Days First)
{
if (First == Days.Monday)
{
yield return Days.Monday;
yield return Days.Tuesday;
yield return Days.Wednesday;
yield return Days.Thursday;
yield return Days.Friday;
yield return Days.Saturday;
yield return Days.Sunday;
}
if (First == Days.Saturday)
{
yield return Days.Saturday;
yield return Days.Sunday;
yield return Days.Monday;
yield return Days.Tuesday;
yield return Days.Wednesday;
yield return Days.Thursday;
yield return Days.Friday;
}
}
In the Enum.GetValues results, casting to int produces the numeric value. Using ToString() produces the friendly name. No other calls to Enum.GetName are needed.
public enum MyEnum
{
FirstWord,
SecondWord,
Another = 5
};
// later in some method
StringBuilder sb = new StringBuilder();
foreach (var val in Enum.GetValues(typeof(MyEnum))) {
int numberValue = (int)val;
string friendyName = val.ToString();
sb.Append("Enum number " + numberValue + " has the name " + friendyName + "\n");
}
File.WriteAllText(@"C:\temp\myfile.txt", sb.ToString());
// Produces the output file contents:
/*
Enum number 0 has the name FirstWord
Enum number 1 has the name SecondWord
Enum number 5 has the name Another
*/
You need to cast the array - the returned array is actually of the requested type, i.e. myEnum[] if you ask for typeof(myEnum):
myEnum[] values = (myEnum[]) Enum.GetValues(typeof(myEnum));
Then values[0] etc
You can simplify this using format strings. I use the following snippet in usage messages:
writer.WriteLine("Exit codes are a combination of the following:");
foreach (ExitCodes value in Enum.GetValues(typeof(ExitCodes)))
{
writer.WriteLine(" {0,4:D}: {0:G}", value);
}
The D format specifier formats the enum value as a decimal. There's also an X specifier that gives hexadecimal output.
The G specifier formats an enum as a string. If the Flags attribute is applied to the enum then combined values are supported as well. There's an F specifier that acts as if Flags is always present.
See Enum.Format().
How about a dictionary list?
Dictionary<string, int> list = new Dictionary<string, int>();
foreach( var item in Enum.GetNames(typeof(MyEnum)) )
{
list.Add(item, (int)Enum.Parse(typeof(MyEnum), item));
}
and of course you can change the dictionary value type to whatever your enum values are.
What about using a foreach loop, maybe you could work with that?
int i = 0;
foreach (var o in values)
{
print(names[i], o);
i++;
}
something like that perhaps?
You can cast that Array to different types of Arrays:
myEnum[] values = (myEnum[])Enum.GetValues(typeof(myEnum));
or if you want the integer values:
int[] values = (int[])Enum.GetValues(typeof(myEnum));
You can iterate those casted arrays of course :)
Source: Stackoverflow.com