感谢大家的所有回答。
最后,我使用了 Rex M 和 adrianbanks 的组合,并添加了我自己的改进,以简化与 ComboBox 的绑定。
之所以需要更改,是因为在处理代码时,我意识到有时我需要能够从组合中排除一个枚举项。
例如。
Enum Complexity
{
// this will be used in filters,
// but not in module where I have to assign Complexity to a field
AllComplexities,
NotSoComplex,
LittleComplex,
Complex,
VeryComplex
}
所以有时我希望选择列表显示除 AllComplexities 之外的所有内容(在添加 - 编辑模块中),而其他时候显示所有内容(在过滤器中)
这就是我所做的:
- 我创建了一个扩展方法,它使用描述属性作为本地化查找键。如果缺少描述属性,我将查找本地化键创建为 EnumName_
枚举值。最后,如果缺少翻译,我只是将基于驼峰式的枚举名称拆分为分隔单词,如 adrianbanks 所示。顺便说一句,TranslationHelper 是 resourceMgr.GetString(...) 的包装器
完整代码如下所示
public static string GetDescription(this System.Enum value)
{
string enumID = string.Empty;
string enumDesc = string.Empty;
try
{
// try to lookup Description attribute
FieldInfo field = value.GetType().GetField(value.ToString());
object[] attribs = field.GetCustomAttributes(typeof(DescriptionAttribute), true);
if (attribs.Length > 0)
{
enumID = ((DescriptionAttribute)attribs[0]).Description;
enumDesc = TranslationHelper.GetTranslation(enumID);
}
if (string.IsNullOrEmpty(enumID) || TranslationHelper.IsTranslationMissing(enumDesc))
{
// try to lookup translation from EnumName_EnumValue
string[] enumName = value.GetType().ToString().Split('.');
enumID = string.Format("{0}_{1}", enumName[enumName.Length - 1], value.ToString());
enumDesc = TranslationHelper.GetTranslation(enumID);
if (TranslationHelper.IsTranslationMissing(enumDesc))
enumDesc = string.Empty;
}
// try to format CamelCase to proper names
if (string.IsNullOrEmpty(enumDesc))
{
Regex capitalLetterMatch = new Regex("\\B[A-Z]", RegexOptions.Compiled);
enumDesc = capitalLetterMatch.Replace(value.ToString(), " $&");
}
}
catch (Exception)
{
// if any error, fallback to string value
enumDesc = value.ToString();
}
return enumDesc;
}
我创建了一个基于 Enum 的通用帮助类,它允许将枚举轻松绑定到 DataSource
public class LocalizableEnum
{
/// <summary>
/// Column names exposed by LocalizableEnum
/// </summary>
public class ColumnNames
{
public const string ID = "EnumValue";
public const string EntityValue = "EnumDescription";
}
}
public class LocalizableEnum<T>
{
private T m_ItemVal;
private string m_ItemDesc;
public LocalizableEnum(T id)
{
System.Enum idEnum = id as System.Enum;
if (idEnum == null)
throw new ArgumentException(string.Format("Type {0} is not enum", id.ToString()));
else
{
m_ItemVal = id;
m_ItemDesc = idEnum.GetDescription();
}
}
public override string ToString()
{
return m_ItemDesc;
}
public T EnumValue
{
get { return m_ID; }
}
public string EnumDescription
{
get { return ToString(); }
}
}
然后我创建了一个通用的静态方法,它返回一个 List>,如下所示
public static List<LocalizableEnum<T>> GetEnumList<T>(object excludeMember)
{
List<LocalizableEnum<T>> list =null;
Array listVal = System.Enum.GetValues(typeof(T));
if (listVal.Length>0)
{
string excludedValStr = string.Empty;
if (excludeMember != null)
excludedValStr = ((T)excludeMember).ToString();
list = new List<LocalizableEnum<T>>();
for (int i = 0; i < listVal.Length; i++)
{
T currentVal = (T)listVal.GetValue(i);
if (excludedValStr != currentVal.ToString())
{
System.Enum enumVal = currentVal as System.Enum;
LocalizableEnum<T> enumMember = new LocalizableEnum<T>(currentVal);
list.Add(enumMember);
}
}
}
return list;
}
和一个包含所有成员的返回列表的包装器
public static List<LocalizableEnum<T>> GetEnumList<T>()
{
return GetEnumList<T>(null);
}
现在让我们把所有东西放在一起并绑定到实际的组合:
// in module where we want to show items with all complexities
// or just filter on one complexity
comboComplexity.DisplayMember = LocalizableEnum.ColumnNames.EnumValue;
comboComplexity.ValueMember = LocalizableEnum.ColumnNames.EnumDescription;
comboComplexity.DataSource = EnumHelper.GetEnumList<Complexity>();
comboComplexity.SelectedValue = Complexity.AllComplexities;
// ....
// and here in edit module where we don't want to see "All Complexities"
comboComplexity.DisplayMember = LocalizableEnum.ColumnNames.EnumValue;
comboComplexity.ValueMember = LocalizableEnum.ColumnNames.EnumDescription;
comboComplexity.DataSource = EnumHelper.GetEnumList<Complexity>(Complexity.AllComplexities);
comboComplexity.SelectedValue = Complexity.VeryComplex; // set default value
要读取选定的值并使用它,我使用如下代码
Complexity selComplexity = (Complexity)comboComplexity.SelectedValue;