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SelectExtensions.DropDownList Method (HtmlHelper, String, IEnumerable<SelectListItem>, String, IDictionary<String, Object>)

Returns a single-selection select element using the specified HTML helper, the name of the form field, the specified list items, an option label, and the specified HTML attributes.

Namespace:  System.Web.Mvc.Html
Assembly:  System.Web.Mvc (in System.Web.Mvc.dll)

Syntax

'Declaration
<ExtensionAttribute> _
Public Shared Function DropDownList ( _
    htmlHelper As HtmlHelper, _
    name As String, _
    selectList As IEnumerable(Of SelectListItem), _
    optionLabel As String, _
    htmlAttributes As IDictionary(Of String, Object) _
) As MvcHtmlString
public static MvcHtmlString DropDownList(
    this HtmlHelper htmlHelper,
    string name,
    IEnumerable<SelectListItem> selectList,
    string optionLabel,
    IDictionary<string, Object> htmlAttributes
)
[ExtensionAttribute]
public:
static MvcHtmlString^ DropDownList(
    HtmlHelper^ htmlHelper, 
    String^ name, 
    IEnumerable<SelectListItem^>^ selectList, 
    String^ optionLabel, 
    IDictionary<String^, Object^>^ htmlAttributes
)

Parameters

  • optionLabel
    Type: System.String
    The text for a default empty item. This parameter can be null reference (Nothing in Visual Basic).

Return Value

Type: System.Web.Mvc.MvcHtmlString
An HTML select element with an option subelement for each item in the list.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type HtmlHelper. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

Exceptions

Exception Condition
ArgumentException

The name parameter is null reference (Nothing in Visual Basic) or empty.

Remarks

The DropDownList method renders an element that enables the user to select one item from a drop-down list. Each item in the list is a SelectListItem object.

The difference between calling the DropDownList method and using a select element is that the DropDownList method is designed to make it easy to bind to view data or model data.

The htmlAttributes parameter consists of an object that contains name/value pairs. The attributes that are specified in the name/value pairs depend on the HTML element that is being rendered. For example, for a select element, you might provide the following anonymous object:

new { id = "select1", size="8" }
New With { .id = "select1",.size="8" }

See Also

Reference

SelectExtensions Class

DropDownList Overload

System.Web.Mvc.Html Namespace