GridView.DataKeys Propriedade
Definição
public:
virtual property System::Web::UI::WebControls::DataKeyArray ^ DataKeys { System::Web::UI::WebControls::DataKeyArray ^ get(); };
[System.ComponentModel.Browsable(false)]
public virtual System.Web.UI.WebControls.DataKeyArray DataKeys { get; }
[<System.ComponentModel.Browsable(false)>]
member this.DataKeys : System.Web.UI.WebControls.DataKeyArray
Public Overridable ReadOnly Property DataKeys As DataKeyArray
Valor da propriedade
Um DataKeyArray que contém a chave de dados de cada linha em um controle GridView.A DataKeyArray that contains the data key of each row in a GridView control.
- Atributos
Exemplos
O exemplo a seguir demonstra como usar a DataKeys propriedade para determinar o valor da chave de dados da linha selecionada em um GridView controle.The following example demonstrates how to use the DataKeys property to determine the data key value of the selected row in a GridView control.
<%@ 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_SelectedIndexChanged(Object sender, EventArgs e)
{
// Determine the index of the selected row.
int index = CustomersGridView.SelectedIndex;
// Display the primary key value of the selected row.
Message.Text = "The primary key value of the selected row is " +
CustomersGridView.DataKeys[index].Value.ToString() + ".";
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView DataKeys Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView DataKeys Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/><br/>
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSource"
autogeneratecolumns="true"
emptydatatext="No data available."
autogenerateselectbutton="true"
datakeynames="CustomerID"
onselectedindexchanged="CustomersGridView_SelectedIndexChanged"
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="CustomersSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
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 CustomersGridView_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
' Determine the index of the selected row.
Dim index As Integer = CustomersGridView.SelectedIndex
' Display the primary key value of the selected row.
Message.Text = "The primary key value of the selected row is " & _
CustomersGridView.DataKeys(index).Value.ToString() & "."
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView DataKeys Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView DataKeys Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/><br/>
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSource"
autogeneratecolumns="true"
emptydatatext="No data available."
autogenerateselectbutton="true"
datakeynames="CustomerID"
onselectedindexchanged="CustomersGridView_SelectedIndexChanged"
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="CustomersSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Comentários
Quando a DataKeyNames propriedade é definida, o GridView controle cria automaticamente um DataKey objeto para cada linha no controle.When the DataKeyNames property is set, the GridView control automatically creates a DataKey object for each row in the control. O DataKey objeto contém os valores do campo ou dos campos especificados na DataKeyNames propriedade.The DataKey object contains the values of the field or fields specified in the DataKeyNames property. Os DataKey objetos são então adicionados à coleção do controle DataKeys .The DataKey objects are then added to the control's DataKeys collection. Use a DataKeys propriedade para recuperar o DataKey objeto de uma linha de dados específica no GridView controle.Use the DataKeys property to retrieve the DataKey object for a specific data row in the GridView control.
Observação
Você pode usar a SelectedDataKey propriedade para recuperar o DataKey objeto para a linha selecionada no momento.You can use the SelectedDataKey property to retrieve the DataKey object for the currently selected row. Você também pode usar a SelectedValue propriedade para recuperar o valor da chave de dados diretamente para a linha selecionada no momento.You can also use the SelectedValue property to retrieve the data key value for the currently selected row directly.