根据&LT添加HTML标签类;选项&GT;在Html.DropDownList [英] Adding html class tag under <option> in Html.DropDownList
本文介绍了根据&LT添加HTML标签类;选项&GT;在Html.DropDownList的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我一直在寻找如何在我的html.dropdownlist添加HTML标签类的答案。这里是code
&LT;%:Html.DropDownList(包标识,新的SelectList(计算机[包]为IEnumerable,包标识,姓名,Model.PackageId))% &GT;
我要添加类的选项中选择元素,这样我可以使用这个链接中选择:
&LT;选择一个id =类别&GT;
&LT;期权价值=1&GT;的One&LT; /选项&GT;
&LT;期权价值=2&GT;二&LT; /选项&GT;
&LT; /选择&GT;
&LT;选择ID =一揽子&GT;
&LT;期权价值=1级=1 - 酮 - 包装1&LT; /选项&GT;
&LT;期权价值=2级=1 - 酮 - 包装2&LT; /选项&GT;
&LT;期权价值=3级=2&GT;二 - 包装1&LT; /选项&GT;
&LT;期权价值=4级=2&GT;二 - 包装2&LT; /选项&GT;
&LT; /选择&GT;$(#系列)链接(#标)。
解决方案
我做这个的DropDownlistFor扩展方法,不使用DropDownList的,但你也许可以明白这一点你自己。这东西大多是从MVC源复制/粘贴。你可以找到源头这里。
公共类ExtendedSelectListItem:SelectListItem
{
公共对象htmlAttributes {搞定;组; }
}公共静态部分类HtmlHelperExtensions
{
公共静态MvcHtmlString ExtendedDropDownListFor&LT;的TModel,TProperty&GT;(此的HtmlHelper&LT;的TModel&GT;的HtmlHelper,防爆pression&LT; Func键&LT;的TModel,TProperty&GT;&GT;前pression,IEnumerable的&LT; ExtendedSelectListItem&GT;选择列表,串optionLabel,对象htmlAttributes)
{
返回SelectInternal(的HtmlHelper,optionLabel,防爆pressionHelper.GetEx pressionText(如pression),选择列表,虚假/ * *的AllowMultiple /,HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes));
} 私有静态MvcHtmlString SelectInternal(此的HtmlHelper的HtmlHelper,串optionLabel,字符串名称,IEnumerable的&LT; ExtendedSelectListItem&GT;选择列表,布尔的AllowMultiple,IDictionary的&LT;字符串对象&gt; htmlAttributes)
{
字符串全名= htmlHelper.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(名);
如果(String.IsNullOrEmpty(全名))
抛出新的ArgumentException(NO NAME); 如果(选择列表== NULL)
抛出新的ArgumentException(不选择列表); 对象设置defaultValue =(的AllowMultiple)? GetModelStateValue(的HtmlHelper,全名的typeof(字符串[])):GetModelStateValue(的HtmlHelper,全名的typeof(字符串)); //如果我们还未使用的ViewData获取项目的完整列表,然后我们需要
//使用参数提供的值之前使用的ViewData提供的值。
如果(设置defaultValue == NULL)
设置defaultValue = htmlHelper.ViewData.Eval(全名); 如果(设置defaultValue!= NULL)
{
IEnumerable的defaultValues =(的AllowMultiple)?设置defaultValue为IEnumerable:新的[] {}设置defaultValue;
IEnumerable的&LT;串GT;从defaultValues对象值选择Convert.ToString(值,CultureInfo.CurrentCulture)值=;
HashSet的&LT;串GT; selectedValues =新的HashSet&LT;串GT;(价值观,StringComparer.OrdinalIgnoreCase);
清单&LT; ExtendedSelectListItem&GT; newSelectList =新的List&LT; ExtendedSelectListItem&GT;(); 的foreach(在选择列表ExtendedSelectListItem项)
{
item.Selected =(item.Value!= NULL)? selectedValues.Contains(item.Value):selectedValues.Contains(item.Text);
newSelectList.Add(项目);
}
选择列表= newSelectList;
} //每个列表项转换为一个&LT;选项&GT;标签
StringBuilder的listItemBuilder =新的StringBuilder(); //使optionLabel是被呈现的第一个项目。
如果(optionLabel!= NULL)
listItemBuilder.Append(ListItemToOption(新ExtendedSelectListItem(){文字= optionLabel,值=的String.Empty,选择= FALSE})); 的foreach(在选择列表ExtendedSelectListItem项)
{
listItemBuilder.Append(ListItemToOption(项目));
} TagBuilder tagBuilder =新TagBuilder(选择)
{
的innerHTML = listItemBuilder.ToString()
};
tagBuilder.MergeAttributes(htmlAttributes);
tagBuilder.MergeAttribute(姓名,全名,真/ * replaceExisting * /);
tagBuilder.GenerateId(全名);
如果(的AllowMultiple)
tagBuilder.MergeAttribute(多,多); //如果有一个名为字段的任何错误,我们添加的CSS属性。
ModelState中的ModelState;
如果(htmlHelper.ViewData.ModelState.TryGetValue(全名,出的ModelState))
{
如果(modelState.Errors.Count大于0)
{
tagBuilder.AddCssClass(HtmlHelper.ValidationInputCssClassName);
}
} tagBuilder.MergeAttributes(htmlHelper.GetUnobtrusiveValidationAttributes(名)); 返回MvcHtmlString.Create(tagBuilder.ToString(TagRenderMode.Normal));
} 内部静态字符串ListItemToOption(ExtendedSelectListItem项)
{
TagBuilder建设者=新TagBuilder(选项)
{
的innerHTML = HttpUtility.HtmlEn code(item.Text)
};
如果(item.Value!= NULL)
{
builder.Attributes [值] = item.Value;
}
如果(item.Selected)
{
builder.Attributes [选择] =选择;
}
builder.MergeAttributes(HtmlHelper.AnonymousObjectToHtmlAttributes(item.htmlAttributes));
返回builder.ToString(TagRenderMode.Normal);
}
}
I've been looking for answers on how to add an HTML class tag on my html.dropdownlist. here is the code
<%: Html.DropDownList("PackageId", new SelectList(ViewData["Packages"] as IEnumerable, "PackageId", "Name", Model.PackageId))%>
I want to add classes for options under the select element so that I can use this chained select :
<select id="category">
<option value="1">One</option>
<option value="2">Two</option>
</select>
<select id="package">
<option value="1" class="1">One - package1</option>
<option value="2" class="1">One - package2</option>
<option value="3" class="2">Two - package1</option>
<option value="4" class="2">Two - package2</option>
</select>
$("#series").chained("#mark");
解决方案
I've done this for the DropDownlistFor extension method, not the DropDownList you use, but you can probably figure that out yourself. This stuff is mostly copy/paste from the MVC sources. You can find the sources here.
public class ExtendedSelectListItem : SelectListItem
{
public object htmlAttributes { get; set; }
}
public static partial class HtmlHelperExtensions
{
public static MvcHtmlString ExtendedDropDownListFor<TModel, TProperty>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TProperty>> expression, IEnumerable<ExtendedSelectListItem> selectList, string optionLabel, object htmlAttributes)
{
return SelectInternal(htmlHelper, optionLabel, ExpressionHelper.GetExpressionText(expression), selectList, false /* allowMultiple */, HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes));
}
private static MvcHtmlString SelectInternal(this HtmlHelper htmlHelper, string optionLabel, string name, IEnumerable<ExtendedSelectListItem> selectList, bool allowMultiple, IDictionary<string, object> htmlAttributes)
{
string fullName = htmlHelper.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(name);
if (String.IsNullOrEmpty(fullName))
throw new ArgumentException("No name");
if (selectList == null)
throw new ArgumentException("No selectlist");
object defaultValue = (allowMultiple) ? GetModelStateValue(htmlHelper, fullName, typeof(string[])) : GetModelStateValue(htmlHelper, fullName, typeof(string));
// If we haven't already used ViewData to get the entire list of items then we need to
// use the ViewData-supplied value before using the parameter-supplied value.
if (defaultValue == null)
defaultValue = htmlHelper.ViewData.Eval(fullName);
if (defaultValue != null)
{
IEnumerable defaultValues = (allowMultiple) ? defaultValue as IEnumerable : new[] { defaultValue };
IEnumerable<string> values = from object value in defaultValues select Convert.ToString(value, CultureInfo.CurrentCulture);
HashSet<string> selectedValues = new HashSet<string>(values, StringComparer.OrdinalIgnoreCase);
List<ExtendedSelectListItem> newSelectList = new List<ExtendedSelectListItem>();
foreach (ExtendedSelectListItem item in selectList)
{
item.Selected = (item.Value != null) ? selectedValues.Contains(item.Value) : selectedValues.Contains(item.Text);
newSelectList.Add(item);
}
selectList = newSelectList;
}
// Convert each ListItem to an <option> tag
StringBuilder listItemBuilder = new StringBuilder();
// Make optionLabel the first item that gets rendered.
if (optionLabel != null)
listItemBuilder.Append(ListItemToOption(new ExtendedSelectListItem() { Text = optionLabel, Value = String.Empty, Selected = false }));
foreach (ExtendedSelectListItem item in selectList)
{
listItemBuilder.Append(ListItemToOption(item));
}
TagBuilder tagBuilder = new TagBuilder("select")
{
InnerHtml = listItemBuilder.ToString()
};
tagBuilder.MergeAttributes(htmlAttributes);
tagBuilder.MergeAttribute("name", fullName, true /* replaceExisting */);
tagBuilder.GenerateId(fullName);
if (allowMultiple)
tagBuilder.MergeAttribute("multiple", "multiple");
// If there are any errors for a named field, we add the css attribute.
ModelState modelState;
if (htmlHelper.ViewData.ModelState.TryGetValue(fullName, out modelState))
{
if (modelState.Errors.Count > 0)
{
tagBuilder.AddCssClass(HtmlHelper.ValidationInputCssClassName);
}
}
tagBuilder.MergeAttributes(htmlHelper.GetUnobtrusiveValidationAttributes(name));
return MvcHtmlString.Create(tagBuilder.ToString(TagRenderMode.Normal));
}
internal static string ListItemToOption(ExtendedSelectListItem item)
{
TagBuilder builder = new TagBuilder("option")
{
InnerHtml = HttpUtility.HtmlEncode(item.Text)
};
if (item.Value != null)
{
builder.Attributes["value"] = item.Value;
}
if (item.Selected)
{
builder.Attributes["selected"] = "selected";
}
builder.MergeAttributes(HtmlHelper.AnonymousObjectToHtmlAttributes(item.htmlAttributes));
return builder.ToString(TagRenderMode.Normal);
}
}
这篇关于根据&LT添加HTML标签类;选项&GT;在Html.DropDownList的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
查看全文