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IHtmlHelper<TModel>.DropDownListFor<TResult> Method

Definition

Returns a single-selection HTML <select> element for the expression. Adds <option> elements based on optionLabel and selectList. Adds a "selected" attribute to an <option> if its Value (if non-null) or Text matches the first non-null value found in: the ModelState entry with full name, or the expression evaluated against Model. See NameFor<TResult>(Expression<Func<TModel,TResult>>) for more information about a "full name".

public:
generic <typename TResult>
 Microsoft::AspNetCore::Html::IHtmlContent ^ DropDownListFor(System::Linq::Expressions::Expression<Func<TModel, TResult> ^> ^ expression, System::Collections::Generic::IEnumerable<Microsoft::AspNetCore::Mvc::Rendering::SelectListItem ^> ^ selectList, System::String ^ optionLabel, System::Object ^ htmlAttributes);
public Microsoft.AspNetCore.Html.IHtmlContent DropDownListFor<TResult> (System.Linq.Expressions.Expression<Func<TModel,TResult>> expression, System.Collections.Generic.IEnumerable<Microsoft.AspNetCore.Mvc.Rendering.SelectListItem> selectList, string optionLabel, object htmlAttributes);
abstract member DropDownListFor : System.Linq.Expressions.Expression<Func<'Model, 'Result>> * seq<Microsoft.AspNetCore.Mvc.Rendering.SelectListItem> * string * obj -> Microsoft.AspNetCore.Html.IHtmlContent
Public Function DropDownListFor(Of TResult) (expression As Expression(Of Func(Of TModel, TResult)), selectList As IEnumerable(Of SelectListItem), optionLabel As String, htmlAttributes As Object) As IHtmlContent

Type Parameters

TResult

The type of the expression result.

Parameters

expression
Expression<Func<TModel,TResult>>

An expression to be evaluated against the current model.

selectList
IEnumerable<SelectListItem>

A collection of SelectListItem objects used to populate the <select> element with <optgroup> and <option> elements. If null, uses the ViewData entry with full name and that entry must be a collection of SelectListItem objects.

optionLabel
String

The text for a default empty item. Does not include such an item if argument is null.

htmlAttributes
Object

An Object that contains the HTML attributes for the <select> element. Alternatively, an IDictionary<TKey,TValue> instance containing the HTML attributes.

Returns

A new IHtmlContent containing the <select> element.

Remarks

Combines HtmlFieldPrefix and the string representation of the expression to set <select> element's "name" attribute. Sanitizes the string representation of the expression to set element's "id" attribute.

Applies to