Language

ListControl.SelectedValue Property

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Gets the value of the selected item in the list control, or selects the item in the list control that contains the specified value.

public:
 virtual property System::String ^ SelectedValue { System::String ^ get(); void set(System::String ^ value); };
[System.ComponentModel.Bindable(true)]
[System.ComponentModel.Browsable(false)]
public virtual string SelectedValue { get; set; }
[System.ComponentModel.Browsable(false)]
[System.ComponentModel.Bindable(true, System.ComponentModel.BindingDirection.TwoWay)]
[System.Web.UI.Themeable(false)]
public virtual string SelectedValue { get; set; }
[]
[]
member this.SelectedValue : string with get, set
[]
[]
[]
member this.SelectedValue : string with get, set
Public Overridable Property SelectedValue As String

Property Value

String

The value of the selected item in the list control. The default is an empty string ("").

Attributes
BindableAttribute BrowsableAttribute ThemeableAttribute

Exceptions

ArgumentOutOfRangeException

The selected value is not in the list of available values and view state or other state has been loaded (a postback has been performed).

Examples

The following example demonstrates how to use the SelectedValue property to select an item in a ListBox control. Notice that this property can also be used to retrieve the value of the selected item.

Important

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.


<%@ Page Language="C#" AutoEventWireup="True" %>


 


     ListControl SelectedValue Example 






   


      
 ListControl SelectedValue Example 

 
      

         Item 1
         Item 2
         Item 3
         Item 4

      

      


      Enter the value of the item to select: 

      

        

      

      



           

   





<%@ Page Language="VB" AutoEventWireup="True" %>


 


     ListControl SelectedValue Example 






   


      
 ListControl SelectedValue Example 

 
      

         Item 1
         Item 2
         Item 3
         Item 4

      

      


      Enter the value of the item to select: 

      

        

Remarks

This property returns the Value property of the selected ListItem. The SelectedValue property is commonly used to determine the value of the selected item in the list control. If multiple items are selected, the value of the selected item with the lowest index is returned. If no item is selected, an empty string ("") is returned.

The SelectedValue property can also be used to select an item in the list control by setting it with the value of the item.

This property cannot be set by themes or style sheet themes. For more information, see ThemeableAttribute and ASP.NET Themes and Skins.

When the selected value is not in the list of available values and a postback is performed, an ArgumentOutOfRangeException exception is thrown. The following example shows how to catch an invalid value before postback occurs:

Me.DropDownList1.Items.Add(New ListItem( Text="Hello", Value="1" ))
If DropDownList1.Items.FindByValue("2") IsNot Nothing Then
    Response.Write("Found")
End If

this.DropDownList1.Items.Add(new ListItem{ Text="Hello", Value="1" });
if(DropDownList1.Items.FindByValue("2") != null) {
    Response.Write("Found");
}

Applies to

See also