private static string GetDisplayValue(Type enumType, object enumValue)
{
if (EnumHelper.IsValidForEnumHelper(enumType))
{
var enumName = Enum.GetName(enumType, enumValue);
var enumField = enumType.GetField(enumName, BindingFlags.Static | BindingFlags.GetField | BindingFlags.Public);
if (enumField != null)
{
var attr = enumField.GetCustomAttribute <DisplayAttribute>(inherit: false);
if (attr != null)
{
string name = attr.GetName();
if (!string.IsNullOrWhiteSpace(name))
{
return(name);
}
}
}
}
return(null);
}
public static MvcHtmlString EnumDropDownListFor <TModel, TEnum>(this HtmlHelper <TModel> htmlHelper,
Expression <Func <TModel, TEnum> > expression, string optionLabel, IDictionary <string, object> htmlAttributes)
{
if (expression == null)
{
throw Error.ArgumentNull("expression");
}
ModelMetadata metadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData);
if (metadata == null)
{
throw Error.Argument("expression", MvcResources.SelectExtensions_InvalidExpressionParameterNoMetadata,
expression.ToString());
}
if (metadata.ModelType == null)
{
throw Error.Argument("expression", MvcResources.SelectExtensions_InvalidExpressionParameterNoModelType,
expression.ToString());
}
if (!EnumHelper.IsValidForEnumHelper(metadata.ModelType))
{
throw Error.Argument("expression", MvcResources.SelectExtensions_InvalidExpressionParameterType,
metadata.ModelType.FullName);
}
// Run through same processing as SelectInternal() to determine selected value and ensure it is included
// in the select list.
string expressionName = ExpressionHelper.GetExpressionText(expression);
string expressionFullName =
htmlHelper.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(expressionName);
Enum currentValue = null;
if (!String.IsNullOrEmpty(expressionFullName))
{
currentValue = htmlHelper.GetModelStateValue(expressionFullName, typeof(Enum)) as Enum;
}
if (currentValue == null && !String.IsNullOrEmpty(expressionName))
{
// Ignore any select list (enumerable with this name) in the view data
currentValue = htmlHelper.ViewData.Eval(expressionName) as Enum;
}
if (currentValue == null)
{
currentValue = metadata.Model as Enum;
}
return(DropDownListHelper(htmlHelper, metadata, expressionName,
EnumHelper.GetSelectList(metadata.ModelType, currentValue), optionLabel, htmlAttributes));
}
public static MvcHtmlString EnumDropDownListFor <TModel, TEnum>(this HtmlHelper <TModel> htmlHelper,
Expression <Func <TModel, TEnum> > expression, string optionLabel, IDictionary <string, object> htmlAttributes)
{
if (expression == null)
{
throw Error.ArgumentNull("expression");
}
ModelMetadata metadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData);
if (metadata == null)
{
throw Error.Argument("expression", MvcResources.SelectExtensions_InvalidExpressionParameterNoMetadata,
expression.ToString());
}
if (metadata.ModelType == null)
{
throw Error.Argument("expression", MvcResources.SelectExtensions_InvalidExpressionParameterNoModelType,
expression.ToString());
}
if (!EnumHelper.IsValidForEnumHelper(metadata.ModelType))
{
string formatString;
if (EnumHelper.HasFlags(metadata.ModelType))
{
formatString = MvcResources.SelectExtensions_InvalidExpressionParameterTypeHasFlags;
}
else
{
formatString = MvcResources.SelectExtensions_InvalidExpressionParameterType;
}
throw Error.Argument("expression", formatString, metadata.ModelType.FullName, "Flags");
}
// Run through same processing as SelectInternal() to determine selected value and ensure it is included
// in the select list.
string expressionName = ExpressionHelper.GetExpressionText(expression);
string expressionFullName =
htmlHelper.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(expressionName);
Enum currentValue = null;
if (!String.IsNullOrEmpty(expressionFullName))
{
currentValue = htmlHelper.GetModelStateValue(expressionFullName, metadata.ModelType) as Enum;
}
if (currentValue == null && !String.IsNullOrEmpty(expressionName))
{
// Ignore any select list (enumerable with this name) in the view data
currentValue = htmlHelper.ViewData.Eval(expressionName) as Enum;
}
if (currentValue == null)
{
currentValue = metadata.Model as Enum;
}
IList <SelectListItem> selectList = EnumHelper.GetSelectList(metadata.ModelType, currentValue);
if (!String.IsNullOrEmpty(optionLabel) && selectList.Count != 0 && String.IsNullOrEmpty(selectList[0].Text))
{
// Were given an optionLabel and the select list has a blank initial slot. Combine.
selectList[0].Text = optionLabel;
// Use the option label just once; don't pass it down the lower-level helpers.
optionLabel = null;
}
return(DropDownListHelper(htmlHelper, metadata, expressionName, selectList, optionLabel, htmlAttributes));
}
