DataGrid.EditItemIndex Propriedade
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.
Obtém ou define o índice de um item no controle DataGrid a ser editado.
public:
virtual property int EditItemIndex { int get(); void set(int value); };public virtual int EditItemIndex { get; set; }member this.EditItemIndex : int with get, setPublic Overridable Property EditItemIndex As IntegerValor da propriedade
O índice de um item no controle DataGrid a ser editado. O valor padrão é -1, que indica que nenhum item no controle DataGrid está sendo editado.
Exceções
O índice especificado é menor que -1.
Exemplos
O exemplo de código a DataGrid seguir demonstra como usar a EditItemIndex propriedade para determinar o item selecionado para edição no controle.
<%@ 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 = new DataTable();
DataView CartView;
void Page_Load(Object sender, EventArgs e)
{
DataRow dr;
if (Session["ShoppingCart"] == null)
{
Cart.Columns.Add(new DataColumn("Qty", typeof(String)));
Cart.Columns.Add(new DataColumn("Item", typeof(String)));
Cart.Columns.Add(new DataColumn("Price", typeof(String)));
Session["ShoppingCart"] = Cart;
// Create sample data.
for (int i = 1; i <= 4; i++)
{
dr = Cart.NewRow();
if (i % 2 != 0)
dr[0] = "2";
else
dr[0] = "1";
dr[1] = "Item " + i.ToString();
dr[2] = (1.23 * (i + 1)).ToString();
Cart.Rows.Add(dr);
}
}
else
Cart = (DataTable)Session["ShoppingCart"];
CartView = new DataView(Cart);
CartView.Sort="Item";
if (!IsPostBack)
BindGrid();
}
void MyDataGrid_Edit(Object sender, DataGridCommandEventArgs e)
{
MyDataGrid.EditItemIndex = e.Item.ItemIndex;
BindGrid();
}
void MyDataGrid_Cancel(Object sender, DataGridCommandEventArgs e)
{
MyDataGrid.EditItemIndex = -1;
BindGrid();
}
void MyDataGrid_Update(Object sender, DataGridCommandEventArgs e)
{
// For bound columns, the edited value is stored in a TextBox.
// The TextBox is the 0th element in the column's cell.
TextBox qtyText = (TextBox)e.Item.Cells[2].Controls[0];
TextBox priceText = (TextBox)e.Item.Cells[3].Controls[0];
String item = e.Item.Cells[1].Text;
String qty = qtyText.Text;
String price = priceText.Text;
DataRow dr;
// With a database, use an update command to update the data. Because
// the data source in this example is an in-memory DataTable, delete the
// old row and replace it with a new one.
// Remove old entry.
CartView.RowFilter = "Item='" + item + "'";
if (CartView.Count > 0)
CartView.Delete(0);
CartView.RowFilter = "";
// Add new entry.
dr = Cart.NewRow();
dr[0] = qty;
dr[1] = item;
dr[2] = price;
Cart.Rows.Add(dr);
MyDataGrid.EditItemIndex = -1;
BindGrid();
}
void BindGrid()
{
MyDataGrid.DataSource = CartView;
MyDataGrid.DataBind();
}
</script>
<head runat="server">
<title>DataGrid Editing Example</title>
</head>
<body style="font: 10pt verdana">
<form id="form1" runat="server">
<h3>DataGrid Editing Example</h3>
<asp:DataGrid id="MyDataGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
Font-Names="Verdana"
Font-Size="8pt"
OnEditCommand="MyDataGrid_Edit"
OnCancelCommand="MyDataGrid_Cancel"
OnUpdateCommand="MyDataGrid_Update"
AutoGenerateColumns="false">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<Columns>
<asp:EditCommandColumn
EditText="Edit"
CancelText="Cancel"
UpdateText="Update"
HeaderText="Edit Command Column">
<ItemStyle Wrap="false">
</ItemStyle>
<HeaderStyle Wrap="false">
</HeaderStyle>
</asp:EditCommandColumn>
<asp:BoundColumn HeaderText="Item"
ReadOnly="true"
DataField="Item"/>
<asp:BoundColumn HeaderText="Quantity"
DataField="Qty"/>
<asp:BoundColumn HeaderText="Price"
DataField="Price"/>
</Columns>
</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 language="VB" runat="server">
Dim Cart As New DataTable
Dim CartView As DataView
Sub Page_Load(sender As Object, e As EventArgs)
Dim dr As DataRow
If Session("ShoppingCart") Is Nothing Then
Cart.Columns.Add(New DataColumn("Qty", GetType(String)))
Cart.Columns.Add(New DataColumn("Item", GetType(String)))
Cart.Columns.Add(New DataColumn("Price", GetType(String)))
Session("ShoppingCart") = Cart
' Create sample data.
Dim i As Integer
For i = 1 To 4
dr = Cart.NewRow()
If i Mod 2 <> 0 Then
dr(0) = "2"
Else
dr(0) = "1"
End If
dr(1) = "Item " & i.ToString()
dr(2) =(1.23 *(i + 1)).ToString()
Cart.Rows.Add(dr)
Next i
Else
Cart = CType(Session("ShoppingCart"), DataTable)
End If
CartView = New DataView(Cart)
CartView.Sort = "Item"
If Not IsPostBack Then
BindGrid()
End If
End Sub 'Page_Load
Sub MyDataGrid_Edit(sender As Object, e As DataGridCommandEventArgs)
MyDataGrid.EditItemIndex = e.Item.ItemIndex
BindGrid()
End Sub 'MyDataGrid_Edit
Sub MyDataGrid_Cancel(sender As Object, e As DataGridCommandEventArgs)
MyDataGrid.EditItemIndex = - 1
BindGrid()
End Sub 'MyDataGrid_Cancel
Sub MyDataGrid_Update(sender As Object, e As DataGridCommandEventArgs)
' For bound columns, the edited value is stored in a TextBox.
' The TextBox is the 0th element in the column's cell.
Dim qtyText As TextBox = CType(e.Item.Cells(2).Controls(0), TextBox)
Dim priceText As TextBox = CType(e.Item.Cells(3).Controls(0), TextBox)
Dim item As String = e.Item.Cells(1).Text
Dim qty As String = qtyText.Text
Dim price As String = priceText.Text
Dim dr As DataRow
' With a database, use an update command to update the data. Because
' the data source in this example is an in-memory DataTable, delete the
' old row and replace it with a new one.
CartView.RowFilter = "Item='" & item & "'"
If CartView.Count > 0 Then
CartView.Delete(0)
End If
CartView.RowFilter = ""
' Add new entry.
dr = Cart.NewRow()
dr(0) = qty
dr(1) = item
dr(2) = price
Cart.Rows.Add(dr)
MyDataGrid.EditItemIndex = - 1
BindGrid()
End Sub 'MyDataGrid_Update
Sub BindGrid()
MyDataGrid.DataSource = CartView
MyDataGrid.DataBind()
End Sub 'BindGrid
</script>
<head runat="server">
<title>DataGrid Editing Example</title>
</head>
<body style="font: 10pt verdana">
<form id="form1" runat="server">
<h3>DataGrid Editing Example</h3>
<asp:DataGrid id="MyDataGrid" runat="server"
BorderColor="black"
BorderWidth="1"
CellPadding="3"
Font-Names="Verdana"
Font-Size="8pt"
OnEditCommand="MyDataGrid_Edit"
OnCancelCommand="MyDataGrid_Cancel"
OnUpdateCommand="MyDataGrid_Update"
AutoGenerateColumns="false">
<HeaderStyle BackColor="#aaaadd">
</HeaderStyle>
<Columns>
<asp:EditCommandColumn
EditText="Edit"
CancelText="Cancel"
UpdateText="Update"
HeaderText="Edit Command Column">
<ItemStyle Wrap="false">
</ItemStyle>
<HeaderStyle Wrap="false">
</HeaderStyle>
</asp:EditCommandColumn>
<asp:BoundColumn HeaderText="Item"
ReadOnly="true"
DataField="Item"/>
<asp:BoundColumn HeaderText="Quantity"
DataField="Qty"/>
<asp:BoundColumn HeaderText="Price"
DataField="Price"/>
</Columns>
</asp:DataGrid>
</form>
</body>
</html>
Comentários
Use a EditItemIndex propriedade quando o DataGrid controle contiver um EditCommandColumn para determinar o índice do item selecionado no DataGrid controle a ser editado.
Essa propriedade também é usada para controlar programaticamente qual item está sendo editado. Definir essa propriedade como um índice de um item no controle habilitará a DataGrid edição de controles para esse item no EditCommandColumn.
Observação
A EditItemIndex propriedade é baseada em zero.
Para cancelar a edição, defina programaticamente essa propriedade como -1.
Cuidado
O texto não é codificado em HTML antes de ser exibido no DataGrid controle. Isso possibilita inserir script em marcas HTML no texto. Se os valores do controle forem provenientes da entrada do usuário, valide os valores para reduzir as vulnerabilidades de segurança.