DetailsView.ItemUpdating Evento

Definizione

Si verifica quando viene fatto clic su un pulsante Aggiorna in un controllo DetailsView, ma prima dell'operazione di aggiornamento.Occurs when an Update button within a DetailsView control is clicked, but before the update operation.

public:
 event System::Web::UI::WebControls::DetailsViewUpdateEventHandler ^ ItemUpdating;
public event System.Web.UI.WebControls.DetailsViewUpdateEventHandler ItemUpdating;
member this.ItemUpdating : System.Web.UI.WebControls.DetailsViewUpdateEventHandler 
Public Custom Event ItemUpdating As DetailsViewUpdateEventHandler 

Esempi

Nell'esempio di codice riportato di seguito viene illustrato ItemUpdating come utilizzare l'evento per codificare in HTML i valori immessi dall'utente prima dell'aggiornamento di un record nell'origine dati.The following code example demonstrates how to use the ItemUpdating event to HTML-encode the values entered by the user before a record is updated in the data source.


<%@ 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 CustomerDetail_ItemInserted(object sender, 
    DetailsViewInsertedEventArgs e)
  {
    // Refresh the GridView control after a new record is inserted 
    // in the DetailsView control.
    CustomersView.DataBind();
  }

  void CustomerDetail_ItemInserting(object sender, 
    DetailsViewInsertEventArgs e)
  {
    // Iterate though the values entered by the user and HTML encode 
    // the values. This helps prevent malicious values from being 
    // stored in the data source.
    for (int i = 0; i < e.Values.Count; i++)
    {
      if (e.Values[i] != null)
      {
        e.Values[i] = Server.HtmlEncode(e.Values[i].ToString());
      }
    }
  }

  void CustomerDetail_ItemUpdated(object sender, 
    DetailsViewUpdatedEventArgs e)
  {
    // Refresh the GridView control after a new record is updated 
    // in the DetailsView control.
    CustomersView.DataBind();
  }

  void CustomerDetail_ItemUpdating(object sender, 
    DetailsViewUpdateEventArgs e)
  {
    // Iterate though the values entered by the user and HTML encode 
    // the values. This helps prevent malicious values from being 
    // stored in the data source.
    for (int i = 0; i < e.NewValues.Count; i++)
    {
      if (e.NewValues[i] != null)
      {
        e.NewValues[i] = Server.HtmlEncode(e.NewValues[i].ToString());
      }
    }
  }

  void CustomerDetail_ItemDeleted(object sender, 
    DetailsViewDeletedEventArgs e)
  {
    // Refresh the GridView control after a new record is updated 
    // in the DetailsView control.
    CustomersView.DataBind();
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>
      DetailsView Example</title>
</head>
<body>
  <form id="Form1" runat="server">
    <h3>
      DetailsView Example</h3>
    <table cellspacing="10">
      <tr>
        <td>
          <!-- Use a GridView control in combination with      -->
          <!-- a DetailsView control to display master-detail  -->
          <!-- information. When the user selects a store from -->
          <!-- GridView control, the customers//s detailed     -->
          <!-- information is displayed in the DetailsView     -->
          <!-- control.                                        -->
          <asp:GridView ID="CustomersView" DataSourceID="Customers" 
            AutoGenerateColumns="False"
            DataKeyNames="CustomerID" runat="server">
            <HeaderStyle BackColor="Blue" ForeColor="White" />
            <Columns>
              <asp:CommandField ShowSelectButton="True" />
              <asp:BoundField DataField="ContactName" 
                HeaderText="ContactName" />
              <asp:BoundField DataField="CompanyName" 
                HeaderText="CompanyName" />
            </Columns>
          </asp:GridView>
        </td>
        <td valign="top">
          <asp:DetailsView ID="CustomerDetail" 
            DataSourceID="Details" AutoGenerateRows="false"
            AutoGenerateInsertButton="true" 
            AutoGenerateEditButton="true" 
            AutoGenerateDeleteButton="true"
            EmptyDataText="No records." 
            DataKeyNames="CustomerID" GridLines="Both" 
            OnItemInserted="CustomerDetail_ItemInserted"
            OnItemInserting="CustomerDetail_ItemInserting" 
            OnItemUpdated="CustomerDetail_ItemUpdated"
            OnItemUpdating="CustomerDetail_ItemUpdating" 
            OnItemDeleted="CustomerDetail_ItemDeleted"
            runat="server">
            <HeaderStyle BackColor="Navy" ForeColor="White" />
            <RowStyle BackColor="White" />
            <AlternatingRowStyle BackColor="LightGray" />
            <EditRowStyle BackColor="LightCyan" />
            <Fields>
              <asp:BoundField DataField="CustomerID" HeaderText="CustomerID" ReadOnly="True" />
              <asp:BoundField DataField="ContactName" HeaderText="ContactName" />
              <asp:BoundField DataField="ContactTitle" HeaderText="ContactTitle" />
              <asp:BoundField DataField="CompanyName" HeaderText="CompanyName" />
              <asp:BoundField DataField="Address" HeaderText="Address" />
              <asp:BoundField DataField="City" HeaderText="City" />
              <asp:BoundField DataField="Region" HeaderText="Region" />
              <asp:BoundField DataField="PostalCode" HeaderText="PostalCode" />
              <asp:BoundField DataField="Country" HeaderText="Country" />
              <asp:BoundField DataField="Phone" HeaderText="Phone" />
              <asp:BoundField DataField="Fax" HeaderText="Fax" />
            </Fields>
          </asp:DetailsView>
        </td>
      </tr>
    </table>
    <!-- This example uses Microsoft SQL Server and connects -->
    <!-- to the Northwind sample database.                   -->
    <!-- It is strongly recommended that each data-bound     -->
    <!-- control uses a separate data source control.        -->
    <asp:SqlDataSource ID="Customers" runat="server" 
      ConnectionString=
        "<%$ ConnectionStrings:NorthwindConnectionString %>"
      SelectCommand="SELECT [CompanyName], [ContactName], [CustomerID] 
        FROM [Customers]">
    </asp:SqlDataSource>
    <!-- Add a filter to the data source control for the     -->
    <!-- DetailsView control to display the details of the   -->
    <!-- store selected in the GridView control.             -->
    <asp:SqlDataSource ID="Details" 
      ConnectionString=
        "<%$ ConnectionStrings:NorthwindConnectionString %>"
      runat="server" 
      SelectCommand="SELECT * FROM [Customers] 
        WHERE ([CustomerID] = @CustomerID)"
      DeleteCommand="DELETE FROM [Customers] 
        WHERE [CustomerID] = @CustomerID"
      InsertCommand="INSERT INTO [Customers] ([CustomerID], 
        [CompanyName], [ContactName], [ContactTitle], [Address], 
        [City], [Region], [PostalCode], [Country], [Phone], [Fax]) 
        VALUES (@CustomerID, @CompanyName, @ContactName, @ContactTitle, 
        @Address, @City, @Region, @PostalCode, @Country, @Phone, @Fax)"
      UpdateCommand="UPDATE [Customers] SET [CompanyName] = @CompanyName, 
        [ContactName] = @ContactName, [ContactTitle] = @ContactTitle, 
        [Address] = @Address, [City] = @City, [Region] = @Region, 
        [PostalCode] = @PostalCode, [Country] = @Country, 
        [Phone] = @Phone, [Fax] = @Fax 
        WHERE [CustomerID] = @CustomerID">
      <SelectParameters>
        <asp:ControlParameter ControlID="CustomersView" 
          Name="CustomerID" PropertyName="SelectedValue"
          Type="String" />
      </SelectParameters>
      <DeleteParameters>
        <asp:Parameter Name="CustomerID" Type="String" />
      </DeleteParameters>
      <UpdateParameters>
        <asp:Parameter Name="CompanyName" Type="String" />
        <asp:Parameter Name="ContactName" Type="String" />
        <asp:Parameter Name="ContactTitle" Type="String" />
        <asp:Parameter Name="Address" Type="String" />
        <asp:Parameter Name="City" Type="String" />
        <asp:Parameter Name="Region" Type="String" />
        <asp:Parameter Name="PostalCode" Type="String" />
        <asp:Parameter Name="Country" Type="String" />
        <asp:Parameter Name="Phone" Type="String" />
        <asp:Parameter Name="Fax" Type="String" />
        <asp:Parameter Name="CustomerID" Type="String" />
      </UpdateParameters>
      <InsertParameters>
        <asp:Parameter Name="CustomerID" Type="String" />
        <asp:Parameter Name="CompanyName" Type="String" />
        <asp:Parameter Name="ContactName" Type="String" />
        <asp:Parameter Name="ContactTitle" Type="String" />
        <asp:Parameter Name="Address" Type="String" />
        <asp:Parameter Name="City" Type="String" />
        <asp:Parameter Name="Region" Type="String" />
        <asp:Parameter Name="PostalCode" Type="String" />
        <asp:Parameter Name="Country" Type="String" />
        <asp:Parameter Name="Phone" Type="String" />
        <asp:Parameter Name="Fax" Type="String" />
      </InsertParameters>
    </asp:SqlDataSource>
  </form>
</body>
</html>
<%@ 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 CustomerDetail_ItemInserted(ByVal sender As Object, _
    ByVal e As DetailsViewInsertedEventArgs)
    ' Refresh the GridView control after a new record is inserted in 
    ' the DetailsView control.
    CustomersView.DataBind()
  End Sub
  
  Sub CustomerDetail_ItemInserting(ByVal sender As Object, _
    ByVal e As DetailsViewInsertEventArgs)
    ' Iterate though the values entered by the user and HTML encode 
    ' the values. This helps prevent malicious values from being 
    ' stored in the data source.
    For i As Integer = 0 To e.Values.Count - 1
      If e.Values(i) IsNot Nothing Then
        e.Values(i) = Server.HtmlEncode(e.Values(i).ToString())
      End If
    Next
  End Sub
  
  Sub CustomerDetail_ItemUpdated(ByVal sender As Object, _
    ByVal e As DetailsViewUpdatedEventArgs)
    ' Refresh the GridView control after a new record is updated 
    ' in the DetailsView control.
    CustomersView.DataBind()
  End Sub
  
  Sub CustomerDetail_ItemUpdating(ByVal sender As Object, _
    ByVal e As DetailsViewUpdateEventArgs)
    ' Iterate though the values entered by the user and HTML encode 
    ' the values. This helps prevent malicious values from being 
    ' stored in the data source.
    For i As Integer = 0 To e.NewValues.Count - 1
      If e.NewValues(i) IsNot Nothing Then
        e.NewValues(i) = Server.HtmlEncode(e.NewValues(i).ToString())
      End If
    Next
  End Sub
  
  Sub CustomerDetail_ItemDeleted(ByVal sender As Object, _
    ByVal e As DetailsViewDeletedEventArgs)
    ' Refresh the GridView control after a new record is updated 
    ' in the DetailsView control.
    CustomersView.DataBind()
  End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>DetailsView Example</title>
</head>
<body>
  <form id="Form1" runat="server">
    <h3>DetailsView Example</h3>
    <table cellspacing="10">
      <tr>
        <td>
          <!-- Use a GridView control in combination with      -->
          <!-- a DetailsView control to display master-detail  -->
          <!-- information. When the user selects a store from -->
          <!-- GridView control, the customers's detailed      -->
          <!-- information is displayed in the DetailsView     -->
          <!-- control.                                        -->
          <asp:GridView ID="CustomersView" DataSourceID="Customers" 
            AutoGenerateColumns="False"
            DataKeyNames="CustomerID" runat="server">
            <HeaderStyle BackColor="Blue" ForeColor="White" />
            <Columns>
              <asp:CommandField ShowSelectButton="True" />
              <asp:BoundField DataField="ContactName" 
                HeaderText="ContactName" />
              <asp:BoundField DataField="CompanyName" 
                HeaderText="CompanyName" />
            </Columns>
          </asp:GridView>
        </td>
        <td valign="top">
          <asp:DetailsView ID="CustomerDetail" DataSourceID="Details" 
            AutoGenerateRows="false"
            AutoGenerateInsertButton="true" 
            AutoGenerateEditButton="true" 
            AutoGenerateDeleteButton="true"
            EmptyDataText="No records." 
            DataKeyNames="CustomerID" GridLines="Both" 
            OnItemInserted="CustomerDetail_ItemInserted"
            OnItemInserting="CustomerDetail_ItemInserting" 
            OnItemUpdated="CustomerDetail_ItemUpdated"
            OnItemUpdating="CustomerDetail_ItemUpdating" 
            OnItemDeleted="CustomerDetail_ItemDeleted"
            runat="server">
            <HeaderStyle BackColor="Navy" ForeColor="White" />
            <RowStyle BackColor="White" />
            <AlternatingRowStyle BackColor="LightGray" />
            <EditRowStyle BackColor="LightCyan" />
            <Fields>
              <asp:BoundField DataField="CustomerID" HeaderText="CustomerID" 
                ReadOnly="True" />
              <asp:BoundField DataField="ContactName" HeaderText="ContactName" />
              <asp:BoundField DataField="ContactTitle" HeaderText="ContactTitle" />
              <asp:BoundField DataField="CompanyName" HeaderText="CompanyName" />
              <asp:BoundField DataField="Address" HeaderText="Address" />
              <asp:BoundField DataField="City" HeaderText="City" />
              <asp:BoundField DataField="Region" HeaderText="Region" />
              <asp:BoundField DataField="PostalCode" HeaderText="PostalCode" />
              <asp:BoundField DataField="Country" HeaderText="Country" />
              <asp:BoundField DataField="Phone" HeaderText="Phone" />
              <asp:BoundField DataField="Fax" HeaderText="Fax" />
            </Fields>
          </asp:DetailsView>
        </td>
      </tr>
    </table>
    <!-- This example uses Microsoft SQL Server and connects -->
    <!-- to the Northwind sample database.                   -->
    <!-- It is strongly recommended that each data-bound     -->
    <!-- control uses a separate data source control.        -->
    <asp:SqlDataSource ID="Customers" runat="server" 
      ConnectionString=
        "<%$ ConnectionStrings:NorthwindConnectionString %>"
      SelectCommand="SELECT [CompanyName], [ContactName], [CustomerID] 
        FROM [Customers]">
    </asp:SqlDataSource>
    <!-- Add a filter to the data source control for the     -->
    <!-- DetailsView control to display the details of the   -->
    <!-- store selected in the GridView control.             -->
    <asp:SqlDataSource ID="Details" 
      ConnectionString=
        "<%$ ConnectionStrings:NorthwindConnectionString %>"
      runat="server" 
      SelectCommand="SELECT * FROM [Customers] 
        WHERE ([CustomerID] = @CustomerID)"
      DeleteCommand="DELETE FROM [Customers] 
        WHERE [CustomerID] = @CustomerID"
      InsertCommand="INSERT INTO [Customers] ([CustomerID], 
        [CompanyName], [ContactName], [ContactTitle], [Address], 
        [City], [Region], [PostalCode], [Country], [Phone], [Fax]) 
        VALUES (@CustomerID, @CompanyName, @ContactName, 
        @ContactTitle, @Address, @City, @Region, @PostalCode, 
        @Country, @Phone, @Fax)"
      UpdateCommand="UPDATE [Customers] SET 
        [CompanyName] = @CompanyName, 
        [ContactName] = @ContactName, [ContactTitle] = @ContactTitle, 
        [Address] = @Address, [City] = @City, [Region] = @Region, 
        [PostalCode] = @PostalCode, [Country] = @Country, 
        [Phone] = @Phone, [Fax] = @Fax 
        WHERE [CustomerID] = @CustomerID">
      <SelectParameters>
        <asp:ControlParameter ControlID="CustomersView" 
          Name="CustomerID" PropertyName="SelectedValue"
          Type="String" />
      </SelectParameters>
      <DeleteParameters>
        <asp:Parameter Name="CustomerID" Type="String" />
      </DeleteParameters>
      <UpdateParameters>
        <asp:Parameter Name="CompanyName" Type="String" />
        <asp:Parameter Name="ContactName" Type="String" />
        <asp:Parameter Name="ContactTitle" Type="String" />
        <asp:Parameter Name="Address" Type="String" />
        <asp:Parameter Name="City" Type="String" />
        <asp:Parameter Name="Region" Type="String" />
        <asp:Parameter Name="PostalCode" Type="String" />
        <asp:Parameter Name="Country" Type="String" />
        <asp:Parameter Name="Phone" Type="String" />
        <asp:Parameter Name="Fax" Type="String" />
        <asp:Parameter Name="CustomerID" Type="String" />
      </UpdateParameters>
      <InsertParameters>
        <asp:Parameter Name="CustomerID" Type="String" />
        <asp:Parameter Name="CompanyName" Type="String" />
        <asp:Parameter Name="ContactName" Type="String" />
        <asp:Parameter Name="ContactTitle" Type="String" />
        <asp:Parameter Name="Address" Type="String" />
        <asp:Parameter Name="City" Type="String" />
        <asp:Parameter Name="Region" Type="String" />
        <asp:Parameter Name="PostalCode" Type="String" />
        <asp:Parameter Name="Country" Type="String" />
        <asp:Parameter Name="Phone" Type="String" />
        <asp:Parameter Name="Fax" Type="String" />
      </InsertParameters>
    </asp:SqlDataSource>
  </form>
</body>
</html>

Commenti

L' ItemUpdating evento viene generato quando si fa clic su un DetailsView pulsante Aggiorna in un controllo, ma prima dell'operazione di aggiornamento.The ItemUpdating event is raised when an Update button within a DetailsView control is clicked, but before the update operation. Questo consente di fornire un gestore eventi che esegue una routine personalizzata, ad esempio l'annullamento dell'operazione di aggiornamento, ogni volta che si verifica questo evento.This allows you to provide an event handler that performs a custom routine, such as canceling the update operation, whenever this event occurs.

Un DetailsViewUpdateEventArgs oggetto viene passato al gestore eventi, che consente di determinare l'indice del record da aggiornare e di indicare che l'operazione di aggiornamento deve essere annullata.A DetailsViewUpdateEventArgs object is passed to the event handler, which allows you to determine the index of the record being updated and to indicate that the update operation should be canceled. Per annullare l'operazione di aggiornamento, impostare Cancel la proprietà truesu.To cancel the update operation, set the Cancel property to true. È inoltre possibile modificare le Keysraccolte OldValues, e NewValues , se necessario, prima che i valori vengano passati all'origine dati.You can also manipulate the Keys, OldValues, and NewValues collections, if necessary, before the values are passed to the data source. Un modo comune per usare queste raccolte è codificare in HTML i valori forniti dall'utente prima che vengano archiviati nell'origine dati.A common way to use these collections is to HTML-encode the values supplied by the user before they are stored in the data source. Questo consente di evitare attacchi intrusivi nello script.This helps to prevent script injection attacks.

Per altre informazioni su come gestire gli eventi, vedere la gestione e generazione di eventi.For more information about how to handle events, see Handling and Raising Events.

Si applica a

Vedi anche