.NET中对枚举的操作
.NET中对枚举的操作下面介绍一个.NET枚举共用类,实现对枚举常用的操作
using System;
using System.ComponentModel;
using System.Reflection;
namespace Common
{
/// <summary>
/// 枚举帮助类
/// </summary>
public static class EnumHelper
{
private static DescriptionAttribute[] GetDescriptAttr(this FieldInfo fieldInfo)
{
if (fieldInfo != null)
{
return (DescriptionAttribute[])fieldInfo.GetCustomAttributes(typeof(DescriptionAttribute), false);
}
return null;
}
/// <summary>
///判断枚举是否包括枚举常数名称
/// </summary>
/// <typeparam name="T">枚举</typeparam>
/// <param name="enumName">枚举常数名称</param>
/// <returns>是否包括枚举常数名称</returns>
public static bool CheckedContainEnumName<T>(string enumName) where T : struct, IConvertible
{
bool _result = false;
if (typeof(T).IsEnum)
{
string[] _enumnName = Enum.GetNames(typeof(T));
if (_enumnName != null)
{
for (int i = 0; i < _enumnName.Length; i++)
{
if (string.Compare(_enumnName[i], enumName, true) == 0)
{
_result = true;
break;
}
}
}
}
return _result;
}
/// <summary>
/// 从枚举中获取Description
/// </summary>
/// <param name="targetEnum">需要获取枚举描述的枚举</param>
/// <returns>描述内容</returns>
public static string GetDescription(this Enum targetEnum)
{
string _description = string.Empty;
FieldInfo _fieldInfo = targetEnum.GetType().GetField(targetEnum.ToString());
DescriptionAttribute[] _attributes = _fieldInfo.GetDescriptAttr();
if (_attributes != null && _attributes.Length > 0)
_description = _attributes[0].Description;
else
_description = targetEnum.ToString();
return _description;
}
/// <summary>
/// 根据Description获取枚举
/// </summary>
/// <typeparam name="T">枚举类型</typeparam>
/// <param name="description">枚举描述</param>
/// <returns>枚举</returns>
public static T ParseEnumDescription<T>(this string description, T defaultValue) where T : struct, IConvertible
{
if (typeof(T).IsEnum)
{
Type _type = typeof(T);
foreach (FieldInfo field in _type.GetFields())
{
DescriptionAttribute[] _description = field.GetDescriptAttr();
if (_description != null && _description.Length > 0)
{
if (string.Compare(_description[0].Description, description, true) == 0)
{
defaultValue = (T)field.GetValue(null);
break;
}
}
else
{
if (string.Compare(field.Name, description, true) == 0)
{
defaultValue = (T)field.GetValue(null);
break;
}
}
}
}
return defaultValue;
}
/// <summary>
/// 将枚举常数名称转换成枚举
/// </summary>
/// <typeparam name="T">枚举</typeparam>
/// <param name="enumName">枚举常数名称</param>
/// <returns></returns>
public static T ParseEnumName<T>(this string enumName) where T : struct, IConvertible
{
return (T)Enum.Parse(typeof(T), enumName, true);
}
}
}
调用方式
public enum AreaMode
{
NONE,
CITY,
TOWN,
ROAD,
CITYTOWN,
TOWNROAD,
CITYROAD,
ALL
}
public class EnumHelperTests
{
public void CheckedContainEnumNameTest()
{
EnumHelper.CheckedContainEnumName<AreaMode>("none");
}
public void GetDescriptionTest()
{
AreaMode.NONE.GetDescription();
}
public void ParseEnumDescriptionTest()
{
EnumHelper.ParseEnumDescription<AreaMode>("NONE", AreaMode.CITYTOWN);
}
public void ParseEnumNameTest()
{
EnumHelper.ParseEnumName<AreaMode>("ALL");
}
}