public static MvcHtmlString LocalizedEnumDropDownListFor <TModel, TProperty>(this HtmlHelper <TModel> htmlHelper
, Expression <Func <TModel, TProperty> > expression
, string optionLabel
, object htmlAttributes)
{
if (expression == null)
{
throw new ArgumentNullException(nameof(expression));
}
ModelMetadata metadata = ModelMetadata.FromLambdaExpression <TModel, TProperty>(expression, htmlHelper.ViewData);
if (metadata == null)
{
throw new ArgumentException("metad data is null", nameof(expression));
}
if (metadata.ModelType == (Type)null)
{
throw new ArgumentException("metadata type is null", nameof(expression));
}
if (!EnumHelper.IsValidForEnumHelper(metadata.ModelType))
{
throw new ArgumentException("value is not enum", nameof(expression));
}
string expressionText = ExpressionHelper.GetExpressionText((LambdaExpression)expression);
string fullHtmlFieldName = htmlHelper.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(expressionText);
Enum @enum = (Enum)null;
if (!string.IsNullOrEmpty(fullHtmlFieldName))
{
@enum = GetModelStateValue(htmlHelper, fullHtmlFieldName, metadata.ModelType) as Enum;
}
if (@enum == null && !string.IsNullOrEmpty(expressionText))
{
@enum = htmlHelper.ViewData.Eval(expressionText) as Enum;
}
if (@enum == null)
{
@enum = metadata.Model as Enum;
}
IList <SelectListItem> selectList = EnumHelperExtension.GetSelectList(metadata.ModelType, @enum);
if (!string.IsNullOrEmpty(optionLabel) && selectList.Count != 0 && string.IsNullOrEmpty(selectList[0].Text))
{
selectList[0].Text = optionLabel;
selectList[0].Value = "";
optionLabel = (string)null;
}
return(htmlHelper.BuildEnumDropDown(metadata, optionLabel, fullHtmlFieldName, selectList, HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes)));
}
public static IList <SelectListItem> GetSelectList(Type type, Enum value)
{
IList <SelectListItem> selectList = EnumHelperExtension.GetSelectList(type);
Type type1 = value == null ? (Type)null : value.GetType();
if (type1 != (Type)null && type1 != type && type1 != Nullable.GetUnderlyingType(type))
{
throw new ArgumentException("value");
}
if (value == null && selectList.Count != 0 && string.IsNullOrEmpty(selectList[0].Value))
{
selectList[0].Selected = true;
}
else
{
string str = value == null ? "0" : value.ToString("d");
bool flag = false;
for (int index = selectList.Count - 1; !flag && index >= 0; --index)
{
SelectListItem selectListItem = selectList[index];
selectListItem.Selected = str == selectListItem.Value;
flag |= selectListItem.Selected;
}
if (!flag)
{
if (selectList.Count != 0 && string.IsNullOrEmpty(selectList[0].Value))
{
selectList[0].Selected = true;
selectList[0].Value = str;
}
else
{
selectList.Insert(0, new SelectListItem()
{
Selected = true,
Text = string.Empty,
Value = str
});
}
}
}
return(selectList);
}