我有以下列举:
public enum AuthenticationMethod
{
FORMS = 1,
WINDOWSAUTHENTICATION = 2,
SINGLESIGNON = 3
}
然而问题是,当我请求AuthenticationMethod时,我需要“FORMS”这个词。表单而不是id
对于这个问题,我找到了以下解决方案(链接):
首先,我需要创建一个自定义属性“StringValue”:
public class StringValue : System.Attribute
{
private readonly string _value;
public StringValue(string value)
{
_value = value;
}
public string Value
{
get { return _value; }
}
}
然后我可以将这个属性添加到我的枚举器中:
public enum AuthenticationMethod
{
[StringValue("FORMS")]
FORMS = 1,
[StringValue("WINDOWS")]
WINDOWSAUTHENTICATION = 2,
[StringValue("SSO")]
SINGLESIGNON = 3
}
当然,我需要一些东西来检索StringValue:
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.GetField(value.ToString());
StringValue[] attrs =
fi.GetCustomAttributes(typeof(StringValue),
false) as StringValue[];
if (attrs.Length > 0)
{
output = attrs[0].Value;
}
return output;
}
}
很好,现在我已经有了工具来获取枚举器的字符串值。
然后我可以这样使用它:
string valueOfAuthenticationMethod = StringEnum.GetStringValue(AuthenticationMethod.FORMS);
好的,现在所有这些工作就像一个魅力,但我发现它有很多工作。我想知道有没有更好的解决办法。
我还尝试了一些字典和静态属性,但这也不是更好。
我发现的Enums国际化或从各自的资源文件获取Enums文本的方法是通过继承DescriptionAttribute类创建一个属性类
public class EnumResourceAttribute : DescriptionAttribute
{
public Type ResourceType { get; private set; }
public string ResourceName { get; private set; }
public int SortOrder { get; private set; }
public EnumResourceAttribute(Type ResourceType,
string ResourceName,
int SortOrder)
{
this.ResourceType = ResourceType;
this.ResourceName = ResourceName;
this.SortOrder = SortOrder;
}
}
创建另一个Static类,为GetString和GetString提供扩展方法。
public static class EnumHelper
{
public static string GetString(this Enum value)
{
EnumResourceAttribute ea =
(EnumResourceAttribute)value.GetType().GetField(value.ToString())
.GetCustomAttributes(typeof(EnumResourceAttribute), false)
.FirstOrDefault();
if (ea != null)
{
PropertyInfo pi = ea.ResourceType
.GetProperty(CommonConstants.ResourceManager);
if (pi != null)
{
ResourceManager rm = (ResourceManager)pi
.GetValue(null, null);
return rm.GetString(ea.ResourceName);
}
}
return string.Empty;
}
public static IList GetStrings(this Type enumType)
{
List<string> stringList = new List<string>();
FieldInfo[] fiArray = enumType.GetFields();
foreach (FieldInfo fi in fiArray)
{
EnumResourceAttribute ea =
(EnumResourceAttribute)fi
.GetCustomAttributes(typeof(EnumResourceAttribute), false)
.FirstOrDefault();
if (ea != null)
{
PropertyInfo pi = ea.ResourceType
.GetProperty(CommonConstants.ResourceManager);
if (pi != null)
{
ResourceManager rm = (ResourceManager)pi
.GetValue(null, null);
stringList.Add(rm.GetString(ea.ResourceName));
}
}
}
return stringList.ToList();
}
}
在Enum的元素上,你可以这样写:
public enum Priority
{
[EnumResourceAttribute(typeof(Resources.AdviceModule), Resources.ResourceNames.AdviceCreateAdviceExternaPriorityMemberHigh, 1)]
High,
[EnumResourceAttribute(typeof(Resources.AdviceModule), Resources.ResourceNames.AdviceCreateAdviceExternaPriorityMemberRoutine, 2)]
Routine
}
Where Resources.ResourceNames.AdviceCreateAdviceExternaPriorityMemberHigh &
resources . resourcename . advicecreateadviceexternaprioritymemberroutine是资源文件中的常量,或者你可以说字符串,其值可以在不同的文化中可用。
如果你在MVC架构中实现你的web应用程序,那么创建一个属性
private IList result;
public IList Result
{
get
{
result = typeof(Priority).GetStrings();
return result;
}
}
在你的.cshtml文件中,你可以像这样将枚举绑定到你的下拉列表:
@Html.DropDownListFor(model => Model.vwClinicalInfo.Priority, new SelectList(Model.Result))
谢谢
Ratnesh
当我遇到这样的情况时,我提出下面的解决方案。
作为一个消费阶级,你可以有
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace MyApp.Dictionaries
{
class Greek
{
public static readonly string Alpha = "Alpha";
public static readonly string Beta = "Beta";
public static readonly string Gamma = "Gamma";
public static readonly string Delta = "Delta";
private static readonly BiDictionary<int, string> Dictionary = new BiDictionary<int, string>();
static Greek() {
Dictionary.Add(1, Alpha);
Dictionary.Add(2, Beta);
Dictionary.Add(3, Gamma);
Dictionary.Add(4, Delta);
}
public static string getById(int id){
return Dictionary.GetByFirst(id);
}
public static int getByValue(string value)
{
return Dictionary.GetBySecond(value);
}
}
}
使用双向字典:
基于此(https://stackoverflow.com/a/255638/986160),假设键将与字典中的单个值相关联,类似于(https://stackoverflow.com/a/255630/986160),但更优雅一些。这个字典也是可枚举的,你可以在整型和字符串之间来回切换。此外,除了这个类,你的代码库中不需要有任何字符串。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;
namespace MyApp.Dictionaries
{
class BiDictionary<TFirst, TSecond> : IEnumerable
{
IDictionary<TFirst, TSecond> firstToSecond = new Dictionary<TFirst, TSecond>();
IDictionary<TSecond, TFirst> secondToFirst = new Dictionary<TSecond, TFirst>();
public void Add(TFirst first, TSecond second)
{
firstToSecond.Add(first, second);
secondToFirst.Add(second, first);
}
public TSecond this[TFirst first]
{
get { return GetByFirst(first); }
}
public TFirst this[TSecond second]
{
get { return GetBySecond(second); }
}
public TSecond GetByFirst(TFirst first)
{
return firstToSecond[first];
}
public TFirst GetBySecond(TSecond second)
{
return secondToFirst[second];
}
public IEnumerator GetEnumerator()
{
return GetFirstEnumerator();
}
public IEnumerator GetFirstEnumerator()
{
return firstToSecond.GetEnumerator();
}
public IEnumerator GetSecondEnumerator()
{
return secondToFirst.GetEnumerator();
}
}
}
我很清楚这个问题已经被回答了,而且OP已经对接受的答案感到满意。但我发现大多数答案,包括公认的答案,都有点复杂。
我有一个项目给了我这样的情况,我能够以这种方式实现它。
首先,你必须考虑枚举名称的大小写:
public enum AuthenticationMethod
{
Forms = 1,
WindowsAuthentication = 2,
SingleSignOn = 3
}
然后,有这个扩展:
using System.Text.RegularExpression;
public static class AnExtension
{
public static string Name(this Enum value)
{
string strVal = value.ToString();
try
{
return Regex.Replace(strVal, "([a-z])([A-Z])", "$1 $2");
}
catch
{
}
return strVal;
}
}
通过这种方法,您可以将每个枚举名称转换为字符串表示形式,每个单词用空格分隔。例:
AuthenticationMethod am = AuthenticationMethod.WindowsAuthentication;
MessageBox.Show(am.Name());
更新:访问这个页面,8年后,在很长一段时间没有接触c#之后,看起来我的答案不再是最好的解决方案。我非常喜欢与属性-函数绑定的转换器解决方案。
如果你正在阅读这篇文章,请确保你也查看了其他答案。(提示:它们在这个上面)
和你们大多数人一样,我非常喜欢Jakub Šturc所选的答案,但我也非常讨厌复制粘贴代码,并尽可能少地这样做。
因此,我决定使用一个EnumBase类,从其中继承/内置大部分功能,从而使我能够专注于内容而不是行为。
这种方法的主要问题是基于这样一个事实,即尽管Enum值是类型安全的实例,但交互是与Enum Class类型的静态实现进行的。
所以在泛型魔法的帮助下,我想我终于得到了正确的组合。
希望有人能像我一样觉得这个有用。
我将从Jakub的例子开始,但是使用继承和泛型:
public sealed class AuthenticationMethod : EnumBase<AuthenticationMethod, int>
{
public static readonly AuthenticationMethod FORMS =
new AuthenticationMethod(1, "FORMS");
public static readonly AuthenticationMethod WINDOWSAUTHENTICATION =
new AuthenticationMethod(2, "WINDOWS");
public static readonly AuthenticationMethod SINGLESIGNON =
new AuthenticationMethod(3, "SSN");
private AuthenticationMethod(int Value, String Name)
: base( Value, Name ) { }
public new static IEnumerable<AuthenticationMethod> All
{ get { return EnumBase<AuthenticationMethod, int>.All; } }
public static explicit operator AuthenticationMethod(string str)
{ return Parse(str); }
}
这里是基类:
using System;
using System.Collections.Generic;
using System.Linq; // for the .AsEnumerable() method call
// E is the derived type-safe-enum class
// - this allows all static members to be truly unique to the specific
// derived class
public class EnumBase<E, T> where E: EnumBase<E, T>
{
#region Instance code
public T Value { get; private set; }
public string Name { get; private set; }
protected EnumBase(T EnumValue, string Name)
{
Value = EnumValue;
this.Name = Name;
mapping.Add(Name, this);
}
public override string ToString() { return Name; }
#endregion
#region Static tools
static private readonly Dictionary<string, EnumBase<E, T>> mapping;
static EnumBase() { mapping = new Dictionary<string, EnumBase<E, T>>(); }
protected static E Parse(string name)
{
EnumBase<E, T> result;
if (mapping.TryGetValue(name, out result))
{
return (E)result;
}
throw new InvalidCastException();
}
// This is protected to force the child class to expose it's own static
// method.
// By recreating this static method at the derived class, static
// initialization will be explicit, promising the mapping dictionary
// will never be empty when this method is called.
protected static IEnumerable<E> All
{ get { return mapping.Values.AsEnumerable().Cast<E>(); } }
#endregion
}
我支持Harvey,但不用const。我可以混合匹配字符串,int,等等。
public class xlsLayout
{
public int xlHeaderRow = 1;
public int xlFirstDataRow = 2;
public int xlSkipLinesBetweenFiles = 1; //so 0 would mean don't skip
public string xlFileColumn = "A";
public string xlFieldColumn = "B";
public string xlFreindlyNameColumn = "C";
public string xlHelpTextColumn = "D";
}
然后……
public partial class Form1 : Form
{
xlsLayout xlLayout = new xlsLayout();
xl.SetCell(xlLayout.xlFileColumn, xlLayout.xlHeaderRow, "File Name");
xl.SetCell(xlLayout.xlFieldColumn, xlLayout.xlHeaderRow, "Code field name");
xl.SetCell(xlLayout.xlFreindlyNameColumn, xlLayout.xlHeaderRow, "Freindly name");
xl.SetCell(xlLayout.xlHelpTextColumn, xlLayout.xlHeaderRow, "Inline Help Text");
}