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DetailsViewDeleteEventArgs.Keys Property

Gets an ordered dictionary of key field name/value pairs that contains the names and values of the key fields of the deleted items.

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

public IOrderedDictionary Keys { get; }

Property Value

Type: System.Collections.Specialized.IOrderedDictionary
An IOrderedDictionary that contains an ordered dictionary of key field name/value pairs used to match the item to delete.

Use the Keys property to access the values of the key field or fields for the record to be deleted. For example, you can use these values to verify the record before deleting it, to change the record to delete, or to keep a log of deleted records.

NoteNote

This property contains only the key fields. To access the name/value pair values for the non-key fields, use the Values property.

The Keys property returns an object that implements the IOrderedDictionary interface. The object contains DictionaryEntry objects that represent the key fields.

NoteNote

As a shortcut, you can also use the indexer of the IOrderedDictionary object to access the key field values. The advantage in using the indexer is that it returns key field values directly.

This property is read-only; however, you can modify the key field values of the IOrderedDictionary object it returns. If you change the key field values, the corresponding record is be deleted from the data source.

The following code example demonstrates how to use the Keys property to access the value of the key field for the record being deleted.


<%@ Page language="C#" %>

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

  void CustomerDetailsView_ItemDeleting(Object sender, 
    DetailsViewDeleteEventArgs e)
  {

    // Get customer ID and name from the Keys and Values
    // properties.
    String keyValue = e.Keys["CustomerID"].ToString();
    String customerName = e.Values["CompanyName"].ToString();

    // Cancel the delete operation if the user attempts to 
    // delete protected record. In this example, records
    // with a customer ID that starts with with "A" cannot
    // be deleted.
    if (keyValue.StartsWith("A"))
    {
      e.Cancel = true;
      MessageLabel.Text = "You cannot delete " +
        customerName + ". This customer is protected.";
    }
    else
    {
      MessageLabel.Text = "Row " + e.RowIndex.ToString() + 
        " deleted.";
    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewDeleteEventArgs Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>DetailsViewDeleteEventArgs Example</h3>

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

          <fieldheaderstyle backcolor="Navy"
            forecolor="White"/>

        </asp:detailsview>

        <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]"
          deletecommand="Delete [Customers] 
            Where [CustomerID]=@CustomerID"
          connectionstring=
            "<%$ ConnectionStrings:NorthWindConnectionString%>" 
          runat="server"/>

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

.NET Framework

Supported in: 4.6, 4, 3.5, 3.0, 2.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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