DetailsView.ItemUpdating Událost
Definice
Důležité
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Vyvolá se při kliknutí na tlačítko Aktualizovat v rámci DetailsView ovládacího prvku, ale před operací aktualizace.
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 Event Type
Příklady
Následující příklad kódu ukazuje, jak použít ItemUpdating událost html kódovat hodnoty zadané uživatelem před aktualizací záznamu ve zdroji dat.
<%@ 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>
Poznámky
Událost ItemUpdating je vyvolána při kliknutí na tlačítko Aktualizovat v rámci DetailsView ovládacího prvku, ale před operací aktualizace. To vám umožní poskytnout obslužnou rutinu události, která provádí vlastní rutinu, například zrušení operace aktualizace, kdykoli dojde k této události.
DetailsViewUpdateEventArgs Objekt je předán obslužné rutině události, která vám umožní určit index aktualizovaného záznamu a označit, že by měla být operace aktualizace zrušena. Pokud chcete operaci aktualizace zrušit, nastavte Cancel vlastnost na true. V případě potřeby můžete také manipulovat s Keyskolekcemi , OldValuesa NewValues před předáním hodnot do zdroje dat. Běžným způsobem použití těchto kolekcí je zakódování hodnot zadaných uživatelem ve formátu HTML před jejich uložením ve zdroji dat. To pomáhá zabránit útokům prostřednictvím injektáže skriptů.
Další informace o zpracování událostí najdete v tématu Zpracování a vyvolávání událostí.
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