DataKey.Value Property

 

Gets the value of the key field at index 0 in the DataKey object.

Namespace:   System.Web.UI.WebControls
Assembly:  System.Web (in System.Web.dll)

Public Overridable ReadOnly Property Value As Object

Property Value

Type: System.Object

The value of the key field at index 0 in the DataKey.

Instead of using the Item or the Values property to retrieve a key field value from a DataKey object, you can use the Value property as a shortcut to determine the value of the key field at index 0 in the DataKey object. This property is commonly used to determine the key field value of a record when the record has only one key field.

System_CAPS_noteNote

If the DataKey object does not contain any key fields, null is returned.

The following code example demonstrates how to use the Value property to determine the primary key value of a record.


<%@ Page language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  Sub CustomerDetailsView_DataBound(ByVal sender As Object, ByVal e As EventArgs) Handles CustomerDetailsView.DataBound

    ' Get the DataKey object for the current record.
    Dim key As DataKey = CustomerDetailsView.DataKey

    ' Display the the value of the key field.
    MessageLabel.Text = "The key field value for the displayed record is " & _
      key.Value.ToString() & "."

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >

  <head runat="server">
    <title>DataKey Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>DataKey Example</h3>

        <asp:detailsview id="CustomerDetailsView"
          datasourceid="DetailsViewSource"
          autogeneraterows="true"
          datakeynames="CustomerID"  
          allowpaging="true"
          runat="server">

        </asp:detailsview>

        <br/>

        <asp:label id="MessageLabel"
          forecolor="Red"
          runat="server"/>

        <!-- This example uses Microsoft SQL Server and connects  -->
        <!-- to the Northwind sample database. Use an ASP.NET     -->
        <!-- expression to retrieve the connection string value   -->
        <!-- from the Web.config file.                            -->
        <asp:sqldatasource id="DetailsViewSource"
          selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
          connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
          runat="server"/>

      </form>
  </body>
</html>

.NET Framework
Available since 2.0
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