GridViewUpdateEventHandler Delegar
Definição
Importante
Algumas informações se referem a produtos de pré-lançamento que podem ser substancialmente modificados antes do lançamento. A Microsoft não oferece garantias, expressas ou implícitas, das informações aqui fornecidas.
Representa o método que manipula o evento RowUpdating de um controle GridView.
public delegate void GridViewUpdateEventHandler(System::Object ^ sender, GridViewUpdateEventArgs ^ e);public delegate void GridViewUpdateEventHandler(object sender, GridViewUpdateEventArgs e);type GridViewUpdateEventHandler = delegate of obj * GridViewUpdateEventArgs -> unitPublic Delegate Sub GridViewUpdateEventHandler(sender As Object, e As GridViewUpdateEventArgs)Parâmetros
- sender
- Object
A fonte do evento.
Um objeto de GridViewUpdateEventArgs que contém os dados do evento.
Exemplos
O exemplo a seguir demonstra como adicionar programaticamente um GridViewUpdateEventHandler delegado ao RowUpdating evento de um GridView controle.
<%@ 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 Page_Load(Object sender, EventArgs e)
{
// Create a new GridView object.
GridView authorGridView = new GridView();
// Set the GridView object's properties.
authorGridView.ID = "AuthorGridView";
authorGridView.DataSourceID = "AuthorsSqlDataSource";
authorGridView.AutoGenerateColumns = true;
authorGridView.AutoGenerateEditButton = true;
authorGridView.DataKeyNames = new String[] {"au_id"};
// Programmatically register the event-handling method.
authorGridView.RowUpdating += new GridViewUpdateEventHandler(this.AuthorsGridView_RowUpdating);
// Add the GridView object to the Controls collection
// of the PlaceHolder control.
GridViewPlaceHolder.Controls.Add(authorGridView);
}
void AuthorsGridView_RowUpdating(Object sender, GridViewUpdateEventArgs e)
{
// HTML-encode all user-provided values before updating
// the data source.
foreach (DictionaryEntry entry in e.NewValues)
{
e.NewValues[entry.Key] = Server.HtmlEncode(entry.Value.ToString());
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridViewUpdateEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewUpdateEventHandler Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<asp:placeholder id="GridViewPlaceHolder"
runat="Server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Pubs sample database. -->
<asp:sqldatasource id="AuthorsSqlDataSource"
selectcommand="SELECT [au_id], [au_lname], [au_fname], [address], [city], [state], [zip] FROM [authors]"
updatecommand="UPDATE authors SET au_lname=@au_lname, au_fname=@au_fname, address=@address, city=@city, state=@state, zip=@zip WHERE (authors.au_id = @au_id)"
connectionstring="server=localhost;database=pubs;integrated security=SSPI"
runat="server">
</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 Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Create a new GridView object.
Dim authorGridView As GridView = New GridView
' Set the GridView object's properties.
authorGridView.ID = "AuthorGridView"
authorGridView.DataSourceID = "AuthorsSqlDataSource"
authorGridView.AutoGenerateColumns = True
authorGridView.AutoGenerateEditButton = True
authorGridView.DataKeyNames = New [String]() {"au_id"}
' Programmatically register the event-handling method.
AddHandler authorGridView.RowUpdating, AddressOf AuthorsGridView_RowUpdating
' Add the GridView object to the Controls collection
' of the PlaceHolder control.
GridViewPlaceHolder.Controls.Add(authorGridView)
End Sub
Sub AuthorsGridView_RowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
' HTML-encode all user-provided values before updating
' the data source.
Dim i As Integer
For i = 0 To e.NewValues.Count - 1
Dim entry As DictionaryEntry = e.NewValues(i)
e.NewValues(entry.Key) = Server.HtmlEncode(entry.Value.ToString())
Next i
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridViewUpdateEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewUpdateEventHandler Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<asp:placeholder id="GridViewPlaceHolder"
runat="Server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Pubs sample database. -->
<asp:sqldatasource id="AuthorsSqlDataSource"
selectcommand="SELECT [au_id], [au_lname], [au_fname], [address], [city], [state], [zip] FROM [authors]"
updatecommand="UPDATE authors SET au_lname=@au_lname, au_fname=@au_fname, address=@address, city=@city, state=@state, zip=@zip WHERE (authors.au_id = @au_id)"
connectionstring="server=localhost;database=pubs;integrated security=SSPI"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
O exemplo a seguir demonstra como adicionar declarativamente um GridViewUpdateEventHandler delegado ao RowUpdating evento de um GridView controle.
<%@ 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 CustomersGridView_RowUpdating(Object sender, GridViewUpdateEventArgs e)
{
// Iterate through the NewValues collection and HTML encode all
// user-provided values before updating the data source.
foreach (DictionaryEntry entry in e.NewValues)
{
e.NewValues[entry.Key] = Server.HtmlEncode(entry.Value.ToString());
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView RowUpdating Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowUpdating Example</h3>
<!-- The GridView control automatically sets the columns -->
<!-- specified in the datakeynames property as read-only. -->
<!-- No input controls are rendered for these columns in -->
<!-- edit mode. -->
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="true"
autogenerateeditbutton="true"
allowpaging="true"
datakeynames="CustomerID"
onrowupdating="CustomersGridView_RowUpdating"
runat="server">
</asp:gridview>
<!-- 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="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</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 CustomersGridView_RowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
' Use the CopyTo method to copy the DictionaryEntry objects in the
' NewValues collection to an array.
Dim records(e.NewValues.Count - 1) As DictionaryEntry
e.NewValues.CopyTo(records, 0)
' Iterate through the array and HTML encode all user-provided values
' before updating the data source.
Dim entry As DictionaryEntry
For Each entry In records
e.NewValues(entry.Key) = Server.HtmlEncode(entry.Value.ToString())
Next
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView RowUpdating Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowUpdating Example</h3>
<!-- The GridView control automatically sets the columns -->
<!-- specified in the datakeynames property as read-only. -->
<!-- No input controls are rendered for these columns in -->
<!-- edit mode. -->
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="true"
autogenerateeditbutton="true"
allowpaging="true"
datakeynames="CustomerID"
onrowupdating="CustomersGridView_RowUpdating"
runat="server">
</asp:gridview>
<!-- 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="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
Comentários
O RowUpdating evento é gerado quando o botão Atualizar de uma linha é clicado, mas antes que o GridView controle atualize a linha. Isso permite que você forneça um método de manipulação de eventos que executa uma rotina personalizada, como cancelar a operação de atualização, sempre que esse evento ocorrer.
Ao criar um GridViewUpdateEventHandler delegado, você identifica o método que manipulará o evento. Para associar o evento ao manipulador de eventos, adicione uma instância do delegado ao evento. O manipulador de eventos é chamado sempre que o evento ocorre, a menos que você remova o representante. Para obter mais informações sobre delegados do manipulador de eventos, consulte Manipulando e levantando eventos.
Métodos de Extensão
| GetMethodInfo(Delegate) |
Obtém um objeto que representa o método representado pelo delegado especificado. |
Aplica-se a
Confira também
Colabore connosco no GitHub
A origem deste conteúdo pode ser encontrada no GitHub, onde também pode criar e rever problemas e pedidos Pull. Para mais informações, consulte o nosso guia do contribuidor.
