ObjectDataSourceView.Updating Evento
Definición
Importante
Parte de la información hace referencia a la versión preliminar del producto, que puede haberse modificado sustancialmente antes de lanzar la versión definitiva. Microsoft no otorga ninguna garantía, explícita o implícita, con respecto a la información proporcionada aquí.
Tiene lugar antes de una operación de Update.
public:
event System::Web::UI::WebControls::ObjectDataSourceMethodEventHandler ^ Updating;
public event System.Web.UI.WebControls.ObjectDataSourceMethodEventHandler Updating;
member this.Updating : System.Web.UI.WebControls.ObjectDataSourceMethodEventHandler
Public Custom Event Updating As ObjectDataSourceMethodEventHandler
Tipo de evento
Ejemplos
En el ejemplo de código siguiente se muestra cómo usar un DropDownList control, TextBox controles y varios ObjectDataSource controles para actualizar los datos.
DropDownList muestra el nombre de , NorthwindEmployee
mientras que los TextBox controles se usan para escribir y actualizar la información de la dirección. Dado que la UpdateParameters colección contiene un ControlParameter objeto enlazado al valor seleccionado de DropDownList, el botón que desencadena la Update operación solo se habilita después de seleccionar un empleado.
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS" Assembly="Samples.AspNet.CS" %>
<%@ Page language="c#" %>
<%@ Import namespace="Samples.AspNet.CS" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
// Add parameters and initialize the user interface
// only if an employee is selected.
private void Page_Load(object sender, EventArgs e)
{
// Be sure the text boxes are initialized with
// data from the currently selected employee.
NorthwindEmployee selectedEmployee = EmployeeLogic.GetEmployee(DropDownList1.SelectedValue);
if (selectedEmployee != null) {
AddressBox.Text = selectedEmployee.Address;
CityBox.Text = selectedEmployee.City;
PostalCodeBox.Text = selectedEmployee.PostalCode;
Button1.Enabled = true;
}
else {
Button1.Enabled = false;
}
}
// Press the button to update.
private void Btn_UpdateEmployee (object sender, CommandEventArgs e) {
ObjectDataSource2.Update();
}
// Dynamically add parameters to the InputParameters collection.
private void NorthwindEmployeeUpdating(object source, ObjectDataSourceMethodEventArgs e) {
// The names of the parameters are the same as
// the variable names for the method that is invoked to
// perform the Update. The InputParameters collection is
// an IDictionary collection of name/value pairs,
// not a ParameterCollection.
e.InputParameters.Add("anID", DropDownList1.SelectedValue);
e.InputParameters.Add("anAddress" ,AddressBox.Text);
e.InputParameters.Add("aCity" ,CityBox.Text);
e.InputParameters.Add("aPostalCode",PostalCodeBox.Text);
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>ObjectDataSource - C# Example</title>
</head>
<body>
<form id="Form1" method="post" runat="server">
<!-- The DropDownList is bound to the first ObjectDataSource. -->
<asp:objectdatasource
id="ObjectDataSource1"
runat="server"
selectmethod="GetAllEmployees"
typename="Samples.AspNet.CS.EmployeeLogic" />
<p><asp:dropdownlist
id="DropDownList1"
runat="server"
datasourceid="ObjectDataSource1"
datatextfield="FullName"
datavaluefield="EmpID"
autopostback="True" /></p>
<!-- The second ObjectDataSource performs the Update. This
preserves the state of the DropDownList, which otherwise
would rebind when the DataSourceChanged event is
raised as a result of an Update operation. -->
<asp:objectdatasource
id="ObjectDataSource2"
runat="server"
updatemethod="UpdateEmployeeWrapper"
onupdating="NorthwindEmployeeUpdating"
typename="Samples.AspNet.CS.EmployeeLogic" />
<p><asp:textbox
id="AddressBox"
runat="server" /></p>
<p><asp:textbox
id="CityBox"
runat="server" /></p>
<p><asp:textbox
id="PostalCodeBox"
runat="server" /></p>
<asp:button
id="Button1"
runat="server"
text="Update Employee"
oncommand="Btn_UpdateEmployee" />
</form>
</body>
</html>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB" Assembly="Samples.AspNet.VB" %>
<%@ Page language="vb" %>
<%@ Import namespace="Samples.AspNet.VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
' Add parameters and initialize the user interface
' only if an employee is selected.
Private Sub Page_Load(sender As Object, e As EventArgs)
' Be sure the text boxes are initialized with
' data from the currently selected employee.
Dim selectedEmployee As NorthwindEmployee
selectedEmployee = EmployeeLogic.GetEmployee(DropDownList1.SelectedValue)
If Not selectedEmployee Is Nothing Then
AddressBox.Text = selectedEmployee.Address
CityBox.Text = selectedEmployee.City
PostalCodeBox.Text = selectedEmployee.PostalCode
Button1.Enabled = True
Else
Button1.Enabled = False
End If
End Sub ' Page_Load
' Press the button to update.
Private Sub Btn_UpdateEmployee (sender As Object, e As CommandEventArgs)
ObjectDataSource2.Update()
End Sub ' Btn_UpdateEmployee
' Dynamically add parameters to the InputParameters collection.
Private Sub NorthwindEmployeeUpdating(source As Object, e As ObjectDataSourceMethodEventArgs)
' The names of the parameters are the same as
' the variable names for the method that is invoked to
' perform the Update. The InputParameters collection is
' an IDictionary collection of name/value pairs,
' not a ParameterCollection.
e.InputParameters.Add("anID", DropDownList1.SelectedValue)
e.InputParameters.Add("anAddress" ,AddressBox.Text)
e.InputParameters.Add("aCity" ,CityBox.Text)
e.InputParameters.Add("aPostalCode",PostalCodeBox.Text)
End Sub ' NorthwindEmployeeUpdating
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>ObjectDataSource - VB Example</title>
</head>
<body>
<form id="Form1" method="post" runat="server">
<!-- The DropDownList is bound to the first ObjectDataSource. -->
<asp:objectdatasource
id="ObjectDataSource1"
runat="server"
selectmethod="GetAllEmployees"
typename="Samples.AspNet.VB.EmployeeLogic" />
<p><asp:dropdownlist
id="DropDownList1"
runat="server"
datasourceid="ObjectDataSource1"
datatextfield="FullName"
datavaluefield="EmpID"
autopostback="True" /></p>
<!-- The second ObjectDataSource performs the Update. This
preserves the state of the DropDownList, which otherwise
would rebind when the DataSourceChanged event is
raised as a result of an Update operation. -->
<asp:objectdatasource
id="ObjectDataSource2"
runat="server"
updatemethod="UpdateEmployeeWrapper"
onupdating="NorthwindEmployeeUpdating"
typename="Samples.AspNet.VB.EmployeeLogic" />
<p><asp:textbox
id="AddressBox"
runat="server" /></p>
<p><asp:textbox
id="CityBox"
runat="server" /></p>
<p><asp:textbox
id="PostalCodeBox"
runat="server" /></p>
<asp:button
id="Button1"
runat="server"
text="Update Employee"
oncommand="Btn_UpdateEmployee" />
</form>
</body>
</html>
Comentarios
Controle el Updating evento para realizar operaciones de inicialización adicionales específicas de la aplicación, validar los valores de los parámetros o cambiar los valores de los parámetros antes de que el ObjectDataSource control realice la Update operación. Los parámetros están disponibles como una IDictionary colección, a la que accede la InputParameters propiedad , que expone el ObjectDataSourceMethodEventArgs objeto .
Para obtener más información acerca de cómo controlar eventos, vea controlar y provocar eventos.