FormViewCommandEventArgs.CommandSource Propiedad
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.
Obtiene el control que provocó el evento.
public:
property System::Object ^ CommandSource { System::Object ^ get(); };public object CommandSource { get; }member this.CommandSource : objPublic ReadOnly Property CommandSource As ObjectValor de propiedad
Objeto Object que representa el control que provocó el evento.
Ejemplos
En el ejemplo siguiente se muestra cómo usar la CommandSource propiedad para tener acceso a las propiedades del control de botón que generó el ItemCommand evento.
Importante
Este ejemplo tiene un cuadro de texto que acepta datos proporcionados por el usuario, lo que puede suponer una amenaza para la seguridad. De forma predeterminada, ASP.NET Web Pages valida que los datos proporcionados por el usuario no incluyen elementos HTML ni de script. Para más información, consulte Información general sobre los ataques mediante scripts.
<%@ 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 ProductFormView_ItemCommand(Object sender, FormViewCommandEventArgs e)
{
// The ItemCommand event is raised when any button within
// the FormView control is clicked. Use the CommandName property
// to determine which button was clicked.
if (e.CommandName == "Add")
{
// Add the product to the ListBox control.
// Use the Row property to retrieve the data row.
FormViewRow row = ProductFormView.Row;
// Retrieve the ProductNameLabel control from
// the data row.
Label productNameLabel = (Label)row.FindControl("ProductNameLabel");
// Retrieve the QuantityTextBox control from
// the data row.
TextBox quantityTextBox = (TextBox)row.FindControl("QuantityTextBox");
if (productNameLabel != null && quantityTextBox != null)
{
// Get the product name from the ProductNameLabel control.
string name = productNameLabel.Text;
// Get the quantity from the QuantityTextBox control.
string quantity = quantityTextBox.Text;
// Create the text to display in the ListBox control.
string description = name + " - " + quantity + " Qty";
// Create a ListItem object using the description and
// product name.
ListItem item = new ListItem(description, name);
// Add the ListItem object to the ListBox.
ProductListBox.Items.Add(item);
// Use the CommandSource property to retrieve
// the Add button. Disable the button after
// the user adds the currently displayed employee
// name to the ListBox control.
Button addButton = (Button)e.CommandSource;
addButton.Enabled = false;
}
}
}
void ProductFormView_DataBound(Object sender, EventArgs e)
{
// To prevent the user from adding duplicate items,
// disable the Add button if the item being bound to the
// FormView control is already in the ListBox control.
// Use the Row property to retrieve the data row.
FormViewRow row = ProductFormView.Row;
// Retrieve the Add button from the data row.
Button addButton = (Button)row.FindControl("AddButton");
// Retrieve the ProductNameLabel control from
// data row.
Label productNameLabel = (Label)row.FindControl("ProductNameLabel");
if (addButton != null && productNameLabel != null)
{
// Get the product name from the ProductNameLabel
// control.
string name = productNameLabel.Text;
// Use the FindByValue method to determine whether
// the ListBox control already contains an entry for
// the item.
ListItem item = ProductListBox.Items.FindByValue(name);
// Disable the Add button if the ListBox control
// already contains the item.
if (item != null)
{
addButton.Enabled = false;
}
else
{
addButton.Enabled = true;
}
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FormViewCommandEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>FormViewCommandEventArgs Example</h3>
<asp:formview id="ProductFormView"
datasourceid="ProductSource"
allowpaging="true"
datakeynames="ProductID"
onitemcommand="ProductFormView_ItemCommand"
ondatabound="ProductFormView_DataBound"
runat="server">
<itemtemplate>
<table>
<tr>
<td style="width:400px">
<b>Description:</b>
<asp:label id="ProductNameLabel"
text='<%# Eval("ProductName") %>'
runat='server'/>
<br/>
<b>Price:</b>
<asp:label id="PriceLabel"
text='<%# Eval("UnitPrice", "{0:c}") %>'
runat='server'/>
<br/>
<asp:textbox id="QuantityTextBox"
width="50px"
maxlength="3"
runat="server"/> Qty
</td>
</tr>
<tr>
<td>
<asp:requiredfieldvalidator ID="QuantityRequiredValidator"
controltovalidate="QuantityTextBox"
text="Please enter a quantity."
display="Static"
runat="server"/>
<br/>
<asp:CompareValidator id="QuantityCompareValidator"
controltovalidate="QuantityTextBox"
text="Please enter an integer value."
display="Static"
type="Integer"
operator="DataTypeCheck"
runat="server"/>
</td>
</tr>
<tr>
<td colspan="2">
<asp:button id="AddButton"
text="Add"
commandname="Add"
runat="server"/>
</td>
</tr>
</table>
</itemtemplate>
</asp:formview>
<br/><br/><hr/>
Items:<br/>
<asp:listbox id="ProductListBox"
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="ProductSource"
selectcommand="Select [ProductID], [ProductName], [UnitPrice] From [Products]"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</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 ProductFormView_ItemCommand(ByVal sender As Object, ByVal e As FormViewCommandEventArgs)
' The ItemCommand event is raised when any button within
' the FormView control is clicked. Use the CommandName property
' to determine which button was clicked.
If e.CommandName = "Add" Then
' Add the product to the ListBox control.
' Use the Row property to retrieve the data row.
Dim row As FormViewRow = ProductFormView.Row
' Retrieve the ProductNameLabel control from
' the data row.
Dim productNameLabel As Label = CType(row.FindControl("ProductNameLabel"), Label)
' Retrieve the QuantityTextBox control from
' the data row.
Dim quantityTextBox As TextBox = CType(row.FindControl("QuantityTextBox"), TextBox)
If productNameLabel IsNot Nothing And quantityTextBox IsNot Nothing Then
' Get the product name from the ProductNameLabel control.
Dim name As String = productNameLabel.Text
' Get the quantity from the QuantityTextBox control.
Dim quantity As String = quantityTextBox.Text
' Create the text to display in the ListBox control.
Dim description As String = name & " - " & quantity & " Qty"
' Create a ListItem object using the description and
' product name.
Dim item As new ListItem(description, name)
' Add the ListItem object to the ListBox.
ProductListBox.Items.Add(item)
' Use the CommandSource property to retrieve
' the Add button. Disable the button after
' the user adds the currently displayed employee
' name to the ListBox control.
Dim addButton As Button = CType(e.CommandSource, Button)
addButton.Enabled = False
End If
End If
End Sub
Sub ProductFormView_DataBound(ByVal sender As Object, ByVal e As EventArgs)
' To prevent the user from adding duplicate items,
' disable the Add button if the item being bound to the
' FormView control is already in the ListBox control.
' Use the Row property to retrieve the data row.
Dim row As FormViewRow = ProductFormView.Row
' Retrieve the Add button from the data row.
Dim addButton As Button = CType(row.FindControl("AddButton"), Button)
' Retrieve the ProductNameLabel control from
' data row.
Dim productNameLabel As Label = CType(row.FindControl("ProductNameLabel"), Label)
If addButton IsNot Nothing And productNameLabel IsNot Nothing Then
' Get the product name from the ProductNameLabel
' control.
Dim name As String = productNameLabel.Text
' Use the FindByValue method to determine whether
' the ListBox control already contains an entry for
' the item.
Dim item As ListItem = ProductListBox.Items.FindByValue(name)
' Disable the Add button if the ListBox control
' already contains the item.
If item IsNot Nothing Then
addButton.Enabled = False
Else
addButton.Enabled = True
End If
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FormViewCommandEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>FormViewCommandEventArgs Example</h3>
<asp:formview id="ProductFormView"
datasourceid="ProductSource"
allowpaging="true"
datakeynames="ProductID"
onitemcommand="ProductFormView_ItemCommand"
ondatabound="ProductFormView_DataBound"
runat="server">
<itemtemplate>
<table>
<tr>
<td style="width:400px">
<b>Description:</b>
<asp:label id="ProductNameLabel"
text='<%# Eval("ProductName") %>'
runat='server'/>
<br/>
<b>Price:</b>
<asp:label id="PriceLabel"
text='<%# Eval("UnitPrice", "{0:c}") %>'
runat='server'/>
<br/>
<asp:textbox id="QuantityTextBox"
width="50px"
maxlength="3"
runat="server"/> Qty
</td>
</tr>
<tr>
<td>
<asp:requiredfieldvalidator ID="QuantityRequiredValidator"
controltovalidate="QuantityTextBox"
text="Please enter a quantity."
display="Static"
runat="server"/>
<br/>
<asp:CompareValidator id="QuantityCompareValidator"
controltovalidate="QuantityTextBox"
text="Please enter an integer value."
display="Static"
type="Integer"
operator="DataTypeCheck"
runat="server"/>
</td>
</tr>
<tr>
<td colspan="2">
<asp:button id="AddButton"
text="Add"
commandname="Add"
runat="server"/>
</td>
</tr>
</table>
</itemtemplate>
</asp:formview>
<br/><br/><hr/>
Items:<br/>
<asp:listbox id="ProductListBox"
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="ProductSource"
selectcommand="Select [ProductID], [ProductName], [UnitPrice] From [Products]"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Comentarios
Utilice la CommandSource propiedad para tener acceso a las propiedades del control que generó el evento. En el caso de un FormViewCommandEventArgs objeto , el control es el botón en el que hizo clic el usuario.
Se aplica a
Consulte también
Colaborar con nosotros en GitHub
El origen de este contenido se puede encontrar en GitHub, donde también puede crear y revisar problemas y solicitudes de incorporación de cambios. Para más información, consulte nuestra guía para colaboradores.
