ListControl.SelectedValue Property
Gets the value of the selected item in the list control, or selects the item in the list control that contains the specified value.
[Visual Basic] Public Overridable Property SelectedValue As String [C#] public virtual string SelectedValue {get; set;} [C++] public: __property virtual String* get_SelectedValue(); public: __property virtual void set_SelectedValue(String*); [JScript] public function get SelectedValue() : String; public function set SelectedValue(String);
Property Value
The value of the selected item in the list control. The default is an empty string ("").
Exceptions
| Exception Type | Condition |
|---|---|
| ArgumentOutOfRangeException | The SelectedValue property is set with a value that does not correspond to an item in the list control. |
Remarks
The SelectedValue property is commonly used to determine the value of the selected item in the list control. 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. If no items in the list control contain the specified value, a System.ArgumentOutOfRangeException is thrown.
Example
[Visual Basic, C#] 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.
[Visual Basic] <!-- The following example demonstrates how to select items in a TextBox. If the item is found in the text box, the item is selected and a message is displayed stating the name of the selected item. If the item is not found, no item is selected and a message is displayed stating that the item was not found. --> <%@ Page Language="VB" AutoEventWireup="True" %> <html> <head> <script runat="server"> Sub Button_Click(sender As Object, e As EventArgs) ' Perform this operation in a try-catch block in case the item is not found. Try List.SelectedValue = ItemTextBox.Text MessageLabel.Text = "You selected " & List.SelectedValue + "." Catch ex As Exception List.SelectedValue = Nothing MessageLabel.Text = "Item not found in ListBox control." End Try End Sub </script> </head> <body> <form runat="server"> <h3> ListControl SelectedValue Example </h3> <asp:ListBox ID="List" runat="server"> <asp:ListItem>Item 1</asp:ListItem> <asp:ListItem>Item 2</asp:ListItem> <asp:ListItem>Item 3</asp:ListItem> <asp:ListItem>Item 4</asp:ListItem> </asp:ListBox> <hr> Enter the value of the item to select: <br> <asp:TextBox ID="ItemTextBox" MaxLength="6" Text="Item 1" runat="server"/> <asp:Button ID="SelectButton" Text="Select Item" OnClick="Button_Click" runat="server"/> <br><br> <asp:Label ID="MessageLabel" runat="server"/> </form> </body> </html> [C#] <!-- The following example demonstrates how to select items in a TextBox. If the item is found in the text box, the item is selected and a message is displayed stating the name of the selected item. If the item is not found, no item is selected and a message is displayed stating that the item was not found. --> <%@ Page Language="C#" AutoEventWireup="True" %> <html> <head> <script runat="server"> void Button_Click(Object sender, EventArgs e) { // Perform this operation in a try-catch block in case the item is not found. try { List.SelectedValue = ItemTextBox.Text; MessageLabel.Text = "You selected " + List.SelectedValue + "."; } catch (Exception ex) { List.SelectedValue = null; MessageLabel.Text = "Item not found in ListBox control."; } } </script> </head> <body> <form runat="server"> <h3> ListControl SelectedValue Example </h3> <asp:ListBox ID="List" runat="server"> <asp:ListItem>Item 1</asp:ListItem> <asp:ListItem>Item 2</asp:ListItem> <asp:ListItem>Item 3</asp:ListItem> <asp:ListItem>Item 4</asp:ListItem> </asp:ListBox> <hr> Enter the value of the item to select: <br> <asp:TextBox ID="ItemTextBox" MaxLength="6" Text="Item 1" runat="server"/> <asp:Button ID="SelectButton" Text="Select Item" OnClick="Button_Click" runat="server"/> <br><br> <asp:Label ID="MessageLabel" runat="server"/> </form> </body> </html>
[C++, JScript] No example is available for C++ or JScript. To view a Visual Basic or C# example, click the Language Filter button
in the upper-left corner of the page.
Requirements
Platforms: Windows 2000, Windows XP Professional, Windows Server 2003 family
See Also
ListControl Class | ListControl Members | System.Web.UI.WebControls Namespace | SelectedItem | SelectedIndex | DataValueField | Items | ListItem | System.ArgumentOutOfRangeException