DataGridItemEventHandler Delegado
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.
Representa el método que controla los eventos ItemCreated y ItemDataBound de un control DataGrid.
public delegate void DataGridItemEventHandler(System::Object ^ sender, DataGridItemEventArgs ^ e);public delegate void DataGridItemEventHandler(object sender, DataGridItemEventArgs e);type DataGridItemEventHandler = delegate of obj * DataGridItemEventArgs -> unitPublic Delegate Sub DataGridItemEventHandler(sender As Object, e As DataGridItemEventArgs)Parámetros
- sender
- Object
Origen del evento.
Objeto DataGridItemEventArgs que contiene los datos del evento.
Ejemplos
En el ejemplo de código siguiente se muestra cómo especificar y codificar un controlador para que el ItemCreated evento muestre el orden en el que se crean los elementos en el DataGrid control .
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script language="C#" runat="server">
DataTable Cart;
DataView CartView;
ICollection CreateDataSource()
{
DataTable dt = new DataTable();
DataRow dr;
dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
for (int i = 0; i < 10; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Item " + i.ToString();
dr[2] = 1.23 * (i+1);
dt.Rows.Add(dr);
}
DataView dv = new DataView(dt);
return dv;
}
void Page_Load(Object sender, EventArgs e)
{
if (!IsPostBack)
{
// Need to load this data only once.
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
}
void Item_Created(Object sender, DataGridItemEventArgs e)
{
Label1.Text = Label1.Text + " " + e.Item.ItemIndex;
}
</script>
<head runat="server">
<title>DataGridItemEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGridItemEventArgs Example</h3>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="true"
OnItemCreated="Item_Created"
AutoGenerateColumns="true">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
</asp:DataGrid>
<br />
<asp:Label id="Label1"
Text="Order of items created: "
runat="server"/>
<br />
<asp:Label id="Label2"
Text="Note: The -1's refer to the header and footer."
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script language="VB" runat="server">
Dim Cart As DataTable
Dim CartView As DataView
Function CreateDataSource() As ICollection
Dim dt As New DataTable()
Dim dr As DataRow
dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
Dim i As Integer
For i = 0 To 9
dr = dt.NewRow()
dr(0) = i
dr(1) = "Item " & i.ToString()
dr(2) = 1.23 *(i + 1)
dt.Rows.Add(dr)
Next i
Dim dv As New DataView(dt)
Return dv
End Function 'CreateDataSource
Sub Page_Load(sender As Object, e As EventArgs)
If Not IsPostBack Then
' Need to load this data only once.
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End If
End Sub 'Page_Load
Sub Item_Created(sender As Object, e As DataGridItemEventArgs)
Label1.Text = Label1.Text & " " & e.Item.ItemIndex
End Sub 'Item_Created
</script>
<head runat="server">
<title>DataGridItemEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGridItemEventArgs Example</h3>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="true"
OnItemCreated="Item_Created"
AutoGenerateColumns="true">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
</asp:DataGrid>
<br />
<asp:Label id="Label1"
Text="Order of items created: "
runat="server"/>
<br />
<asp:Label id="Label2"
Text="Note: The -1's refer to the header and footer."
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" Debug="true" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
ICollection CreateDataSource()
{
// Create sample data for the DataGrid control.
DataTable dt = new DataTable();
DataRow dr;
// Define the columns of the table.
dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
dt.Columns.Add(new DataColumn("StringValue", typeof(String)));
dt.Columns.Add(new DataColumn("CurrencyValue", typeof(Double)));
// Populate the table with sample values.
for (int i=0; i<=10; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Item " + i.ToString();
dr[2] = 1.23 * (i + 1);
dt.Rows.Add(dr);
}
DataView dv = new DataView(dt);
return dv;
}
void Page_Load(Object sender, EventArgs e)
{
// Load sample data only once, when the page is first loaded.
if (!IsPostBack)
{
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
}
void Item_Bound(Object sender, DataGridItemEventArgs e)
{
// Use the ItemDataBound event to customize the DataGrid control.
// The ItemDataBound event allows you to access the data before
// the item is displayed in the control. In this example, the
// ItemDataBound event is used to format the items in the
// CurrencyColumn in currency format.
if((e.Item.ItemType == ListItemType.Item) ||
(e.Item.ItemType == ListItemType.AlternatingItem))
{
// Retrieve the text of the CurrencyColumn from the DataGridItem
// and convert the value to a Double.
Double Price = Convert.ToDouble(e.Item.Cells[2].Text);
// Format the value as currency and redisplay it in the DataGrid.
e.Item.Cells[2].Text = Price.ToString("c");
}
}
</script>
<head runat="server">
<title>DataGrid ItemDataBound Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid ItemDataBound Example</h3>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="true"
OnItemDataBound="Item_Bound">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
</asp:DataGrid>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
Function CreateDataSource() As ICollection
' Create sample data for the DataGrid control.
Dim dt As DataTable = New DataTable()
Dim dr As DataRow
' Define the columns of the table.
dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
' Populate the table with sample values.
Dim i As Integer
For i=0 To 10
dr = dt.NewRow()
dr(0) = i
dr(1) = "Item " & i.ToString()
dr(2) = 1.23 * (i + 1)
dt.Rows.Add(dr)
Next i
Dim dv As DataView = New DataView(dt)
return dv
End Function
Sub Page_Load(sender As Object, e As EventArgs)
' Load sample data only once, when the page is first loaded.
If Not IsPostBack Then
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End If
End Sub
Sub Item_Bound(sender As Object, e As DataGridItemEventArgs)
' Use the ItemDataBound event to customize the DataGrid control.
' The ItemDataBound event allows you to access the data before
' the item is displayed in the control. In this example, the
' ItemDataBound event is used to format the items in the
' CurrencyColumn in currency format.
If e.Item.ItemType = ListItemType.Item Or _
e.Item.ItemType = ListItemType.AlternatingItem Then
' Retrieve the text of the CurrencyColumn from the DataGridItem
' and convert the value to a Double.
Dim Price As Double = Convert.ToDouble(e.Item.Cells(2).Text)
' Format the value as currency and redisplay it in the DataGrid.
e.Item.Cells(2).Text = Price.ToString("c")
End If
End Sub
</script>
<head runat="server">
<title>DataGrid ItemDataBound Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid ItemDataBound Example</h3>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="true"
OnItemDataBound="Item_Bound">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
</asp:DataGrid>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
ICollection CreateDataSource()
{
// Create sample data for the DataGrid control.
DataTable dt = new DataTable();
DataRow dr;
// Define the columns of the table.
dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
dt.Columns.Add(new DataColumn("StringValue", typeof(String)));
dt.Columns.Add(new DataColumn("CurrencyValue", typeof(Double)));
// Populate the table with sample values.
for (int i=0; i<=10; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Item " + i.ToString();
dr[2] = 1.23 * (i + 1);
dt.Rows.Add(dr);
}
DataView dv = new DataView(dt);
return dv;
}
void Page_Load(Object sender, EventArgs e)
{
// Manually register the event-handling method for the
// ItemDataBound event of the DataGrid control.
ItemsGrid.ItemDataBound +=
new DataGridItemEventHandler(this.Item_Bound);
// Load sample data only once, when the page is first loaded.
if (!IsPostBack)
{
ItemsGrid.DataSource = CreateDataSource();
ItemsGrid.DataBind();
}
}
void Item_Bound(Object sender, DataGridItemEventArgs e)
{
// Use the ItemDataBound event to customize the DataGrid control.
// The ItemDataBound event allows you to access the data before
// the item is displayed in the control. In this example, the
// ItemDataBound event is used to format the items in the
// CurrencyColumn in currency format.
if((e.Item.ItemType == ListItemType.Item) ||
(e.Item.ItemType == ListItemType.AlternatingItem))
{
// Retrieve the text of the CurrencyColumn from the DataGridItem
// and convert the value to a Double.
Double Price = Convert.ToDouble(e.Item.Cells[2].Text);
// Format the value as currency and redisplay it in the DataGrid.
e.Item.Cells[2].Text = Price.ToString("c");
}
}
</script>
<head runat="server">
<title>DataGrid ItemDataBound Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid ItemDataBound Example</h3>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="true">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
</asp:DataGrid>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
Function CreateDataSource() As ICollection
' Create sample data for the DataGrid control.
Dim dt As DataTable = New DataTable()
Dim dr As DataRow
' Define the columns of the table.
dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
' Populate the table with sample values.
Dim i As Integer
For i=0 To 10
dr = dt.NewRow()
dr(0) = i
dr(1) = "Item " & i.ToString()
dr(2) = 1.23 * (i + 1)
dt.Rows.Add(dr)
Next i
Dim dv As DataView = New DataView(dt)
return dv
End Function
Sub Page_Load(sender As Object, e As EventArgs)
' Manually register the event-handling method for the
' ItemDataBound event of the DataGrid control.
AddHandler ItemsGrid.ItemDataBound, AddressOf Item_Bound
' Load sample data only once, when the page is first loaded.
If Not IsPostBack Then
ItemsGrid.DataSource = CreateDataSource()
ItemsGrid.DataBind()
End If
End Sub
Sub Item_Bound(sender As Object, e As DataGridItemEventArgs)
' Use the ItemDataBound event to customize the DataGrid control.
' The ItemDataBound event allows you to access the data before
' the item is displayed in the control. In this example, the
' ItemDataBound event is used to format the items in the
' CurrencyColumn in currency format.
If e.Item.ItemType = ListItemType.Item Or _
e.Item.ItemType = ListItemType.AlternatingItem Then
' Retrieve the text of the CurrencyColumn from the DataGridItem
' and convert the value to a Double.
Dim Price As Double = Convert.ToDouble(e.Item.Cells(2).Text)
' Format the value as currency and redisplay it in the DataGrid.
e.Item.Cells(2).Text = Price.ToString("c")
End If
End Sub
</script>
<head runat="server">
<title>DataGrid ItemDataBound Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DataGrid ItemDataBound Example</h3>
<asp:DataGrid id="ItemsGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
ShowFooter="true">
<HeaderStyle BackColor="#00aaaa">
</HeaderStyle>
<FooterStyle BackColor="#00aaaa">
</FooterStyle>
</asp:DataGrid>
</form>
</body>
</html>
Comentarios
El ItemCreated evento se genera cuando se crea un elemento del DataGrid control.
El ItemDataBound evento se genera cuando un elemento del DataGrid control está enlazado a un origen de datos.
Cuando se crea un delegado DataGridItemEventHandler, se identifica el método que controlará el evento. Para asociar el evento al controlador, se debe agregar una instancia del delegado al evento. Siempre que se produce el evento, se llama a su controlador, a menos que se quite el delegado. Para obtener más información sobre los delegados del controlador de eventos, vea Control y generación de eventos.
Métodos de extensión
| GetMethodInfo(Delegate) |
Obtiene un objeto que representa el método representado por el delegado especificado. |
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.
Comentarios
Próximamente: A lo largo de 2024 iremos eliminando gradualmente GitHub Issues como mecanismo de comentarios sobre el contenido y lo sustituiremos por un nuevo sistema de comentarios. Para más información, vea: https://aka.ms/ContentUserFeedback.
Enviar y ver comentarios de