HtmlHelper.DropDownList Method (String, String, IEnumerable<SelectListItem>, IDictionary<String, Object>)
Returns an HTML drop-down list control that has the specified name and custom attributes defined by an attribute dictionary, and that contains the specified list items and default item.
Namespace: System.Web.WebPages.Html
Assembly: System.Web.WebPages (in System.Web.WebPages.dll)
Syntax
'Declaration
Public Function DropDownList ( _
name As String, _
defaultOption As String, _
selectList As IEnumerable(Of SelectListItem), _
htmlAttributes As IDictionary(Of String, Object) _
) As IHtmlString
'Usage
Dim instance As HtmlHelper
Dim name As String
Dim defaultOption As String
Dim selectList As IEnumerable(Of SelectListItem)
Dim htmlAttributes As IDictionary(Of String, Object)
Dim returnValue As IHtmlString
returnValue = instance.DropDownList(name, _
defaultOption, selectList, htmlAttributes)
public IHtmlString DropDownList(
string name,
string defaultOption,
IEnumerable<SelectListItem> selectList,
IDictionary<string, Object> htmlAttributes
)
public:
IHtmlString^ DropDownList(
String^ name,
String^ defaultOption,
IEnumerable<SelectListItem^>^ selectList,
IDictionary<String^, Object^>^ htmlAttributes
)
member DropDownList :
name:string *
defaultOption:string *
selectList:IEnumerable<SelectListItem> *
htmlAttributes:IDictionary<string, Object> -> IHtmlString
public function DropDownList(
name : String,
defaultOption : String,
selectList : IEnumerable<SelectListItem>,
htmlAttributes : IDictionary<String, Object>
) : IHtmlString
Parameters
- name
Type: System.String
The value to assign to the name attribute of the HTML select element.
- defaultOption
Type: System.String
The text to display for the default option in the list.
- selectList
Type: System.Collections.Generic.IEnumerable<SelectListItem>
A list of SelectListItem instances that are used to populate the list.
- htmlAttributes
Type: System.Collections.Generic.IDictionary<String, Object>
The names and values of custom attributes for the element.
Return Value
Type: System.Web.IHtmlString
The HTML markup that represents the drop-down list control.
Exceptions
Exception | Condition |
---|---|
ArgumentException | name is null reference (Nothing in Visual Basic) or empty. |
Remarks
The returned markup consists of an HTML select element in the following form:
<select name="name" ...htmlAttributes...>
<option>defaultOption</option>
<option value="selectList[0].Value">selectList[0].Text</option>
<option value="selectList[1].Value">selectList[1].Text</option>
...
</select>
The default option appears at the start of the list and its value is empty. A default option is used to communicate that no option is being chosen from the list, such as when the drop-down control represents an optional parameter.