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DetailsView.ItemUpdating Событие

Определение

Происходит при нажатии кнопки обновления в элементе управления DetailsView перед выполнением операции обновления.

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 

Тип события

Примеры

В следующем примере кода показано, как использовать ItemUpdating событие для html-кодирования значений, введенных пользователем перед обновлением записи в источнике данных.


<%@ 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>

Комментарии

Событие ItemUpdating возникает при нажатии кнопки Обновить в элементе DetailsView управления, но перед операцией обновления. Это позволяет предоставить обработчик событий, который выполняет пользовательскую подпрограмму, например отмену операции обновления, при каждом возникновении этого события.

Объект DetailsViewUpdateEventArgs передается обработчику событий, что позволяет определить индекс обновляемой записи и указать, что операция обновления должна быть отменена. Чтобы отменить операцию обновления, задайте для Cancel свойства значение true. При необходимости можно также управлять коллекциями Keys, OldValuesи NewValues перед передачей значений в источник данных. Распространенный способ использования этих коллекций — кодирование значений в ФОРМАТЕ HTML, предоставленных пользователем перед их сохранением в источнике данных. Это помогает предотвратить атаки путем внедрения скриптов.

Дополнительные сведения об обработке событий см. в разделе Обработка и создание событий.

Применяется к

См. также раздел