DetailsViewUpdatedEventArgs.OldValues Property

 

Gets a dictionary that contains the original field name/value pairs for the updated record.

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

Public ReadOnly Property OldValues As IOrderedDictionary

Property Value

Type: System.Collections.Specialized.IOrderedDictionary

An IOrderedDictionary that contains a dictionary of the original field name/value pairs for the updated record.

Use the OldValues property to access the original field values for the updated record. For example, you can use these values to keep a log of updated records.

The OldValues property returns an object that implements the IOrderedDictionary interface. The object contains DictionaryEntry objects that represent the fields of the updated record.

System_CAPS_noteNote

As a shortcut, you can also use the indexer of the IOrderedDictionary object to access the field values directly.

The following code example demonstrates how to use the OldValues property to access the original values of the non-key fields for the updated 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_ItemUpdated(ByVal sender As Object, ByVal e As DetailsViewUpdatedEventArgs)

    ' Use the Exception property to determine whether an exception
    ' occurred during the insert operation.
    If e.Exception Is Nothing Then

      ' Use the Values property to get the value entered by 
      ' the user for the CompanyName field.
      Dim keyFieldValue As String = e.Keys("CustomerID").ToString()

      ' Display a confirmation message.
      MessageLabel.Text = "Record " & keyFieldValue & _
        " updated successfully. "

      ' Display the old and new values.
      DisplayValues(e)

      If e.AffectedRows = 1 Then

        MessageLabel.Text &= e.AffectedRows.ToString() & _
          " record updated."

      Else

        MessageLabel.Text &= e.AffectedRows.ToString() & _
          " records updated."

      End If

    Else

      ' Insert the code to handle the exception.
      MessageLabel.Text = e.Exception.Message

      ' Use the ExceptionHandled property to indicate that the 
      ' exception is already handled.
      e.ExceptionHandled = True

      ' When an exception occurs, keep the DetailsView
      ' control in edit mode.
      e.KeepInEditMode = True

    End If

  End Sub

  Sub DisplayValues(ByVal e As DetailsViewUpdatedEventArgs)

    MessageLabel.Text &= "<br/></br>"

    ' Iterate through the OldValue and NewValues
    ' properties and display the values.
    Dim i As Integer

    For i = 0 To e.OldValues.Count - 1

      MessageLabel.Text &= "Old Value=" & e.OldValues(i).ToString() & _
        ", New Value=" & e.NewValues(i).ToString() & "<br/>"

    Next

    MessageLabel.Text &= "</br>"

  End Sub

</script>

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

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

      <h3>DetailsViewUpdatedEventArgs Example</h3>

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

          <pagersettings position="Bottom"/> 

        </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]"
          updatecommand="Update [Customers] Set 
          [CompanyName]=@CompanyName, [Address]=@Address, 
          [City]=@City, [PostalCode]=@PostalCode, 
          [Country]=@Country 
          Where [CustomerID]=@CustomerID"
          connectionstring=
          "<%$ ConnectionStrings:NorthWindConnectionString%>" 
          runat="server"/>

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

.NET Framework
Available since 2.0
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