SelectExtensions.DropDownList Method (HtmlHelper, String, IEnumerable(Of SelectListItem), 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)
'Declaration <ExtensionAttribute> _ Public Shared Function DropDownList ( _ htmlHelper As HtmlHelper, _ name As String, _ selectList As IEnumerable(Of SelectListItem), _ optionLabel As String, _ htmlAttributes As Object _ ) As MvcHtmlString 'Usage Dim htmlHelper As HtmlHelper Dim name As String Dim selectList As IEnumerable(Of SelectListItem) Dim optionLabel As String Dim htmlAttributes As Object Dim returnValue As MvcHtmlString returnValue = htmlHelper.DropDownList(name, _ selectList, optionLabel, htmlAttributes)
Parameters
- htmlHelper
- Type: System.Web.Mvc.HtmlHelper
The HTML helper instance that this method extends.
- name
- Type: System.String
The name of the form field to return.
- selectList
- Type: System.Collections.Generic.IEnumerable(Of SelectListItem)
A collection of SelectListItem objects that are used to populate the drop-down list.
- optionLabel
- Type: System.String
The text for a default empty item. This parameter can be Nothing.
- htmlAttributes
- Type: System.Object
An object that contains the HTML attributes to set for the element.
Return Value
Type: System.Web.Mvc.MvcHtmlStringAn 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 https://msdn.microsoft.com/en-us/library/bb384936(v=vs.108) or https://msdn.microsoft.com/en-us/library/bb383977(v=vs.108).| Exception | Condition |
|---|---|
| ArgumentException | The name parameter is Nothing or empty. |
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: