DetailsView.DataKey Propriedade
Definição
Importante
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Obtém um objeto DataKey que representa a chave primária do registro exibido.
public:
virtual property System::Web::UI::WebControls::DataKey ^ DataKey { System::Web::UI::WebControls::DataKey ^ get(); };
[System.ComponentModel.Browsable(false)]
public virtual System.Web.UI.WebControls.DataKey DataKey { get; }
[<System.ComponentModel.Browsable(false)>]
member this.DataKey : System.Web.UI.WebControls.DataKey
Public Overridable ReadOnly Property DataKey As DataKey
Valor da propriedade
Um DataKey que representa a chave primária do registro exibido.
- Atributos
Exemplos
O exemplo de código a seguir demonstra como usar a DataKey propriedade para determinar o campo de chave e o valor correspondente para o registro atual.
<%@ 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 CustomerDetailView_ItemUpdated(Object sender,
DetailsViewUpdatedEventArgs e)
{
// Create a dictionary that contains the key fields and values using
// the AllValues method of the DataKey object contained in the DataKey
// property.
IOrderedDictionary keyList = CustomerDetailView.DataKey.Values;
// Get the ArrayList objects that represent the key fields and values.
ArrayList keys = (ArrayList)keyList.Keys;
ArrayList values = (ArrayList)keyList.Values;
// Get the key field and value for the current record.
String keyField = keys[0].ToString();
String keyValue = values[0].ToString();
// Log the update operation using the key field and value.
LogUpdate(keyField, keyValue);
}
void LogUpdate(String keyField, String keyValue)
{
// Insert code to log the update operation.
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsView DataKey Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>DetailsView DataKey Example</h3>
<asp:detailsview id="CustomerDetailView"
datasourceid="DetailsViewSource"
datakeynames="CustomerID"
autogeneraterows="true"
autogenerateeditbutton="true"
allowpaging="true"
onitemupdated="CustomerDetailView_ItemUpdated"
runat="server">
<headerstyle backcolor="Navy"
forecolor="White"/>
</asp:detailsview>
<!-- 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="DetailsViewSource" runat="server"
ConnectionString=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
InsertCommand="INSERT INTO [Customers]([CustomerID],
[CompanyName], [Address], [City], [PostalCode], [Country])
VALUES (@CustomerID, @CompanyName, @Address, @City,
@PostalCode, @Country)"
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">
</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 CustomerDetailView_ItemUpdated(ByVal sender As Object, _
ByVal e As DetailsViewUpdatedEventArgs)
' Create a dictionary that contains the key fields and values
' using the AllValues method of the DataKey object contained
' in the DataKey property.
Dim keyList As IOrderedDictionary = _
CustomerDetailsView.DataKey.Values
' Get the ArrayList objects that represent the key fields
' and values.
Dim keys As ArrayList = CType(keyList.Keys, ArrayList)
Dim values As ArrayList = CType(keyList.Values, ArrayList)
' Get the key field and value for the current record.
Dim keyField As String = keys(0).ToString()
Dim keyValue As String = values(0).ToString()
' Log the update operation using the key field and value.
LogUpdate(keyField, keyValue)
End Sub
Sub LogUpdate(ByVal keyField As String, ByVal keyValue As String)
' Insert code to log the update operation.
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>
DetailsView DataKey Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>
DetailsView DataKey Example</h3>
<asp:DetailsView ID="CustomerDetailsView"
DataSourceID="DetailsViewSource"
DataKeyNames="CustomerID"
AutoGenerateRows="true"
AutoGenerateEditButton="true"
AllowPaging="true"
OnItemUpdated="CustomerDetailView_ItemUpdated"
runat="server">
<HeaderStyle BackColor="Navy" ForeColor="White" />
</asp:DetailsView>
<!-- 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="DetailsViewSource" runat="server"
ConnectionString=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
InsertCommand="INSERT INTO [Customers]([CustomerID],
[CompanyName], [Address], [City], [PostalCode], [Country])
VALUES (@CustomerID, @CompanyName, @Address, @City,
@PostalCode, @Country)"
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"></asp:SqlDataSource>
</form>
</body>
</html>
Comentários
Quando a DataKeyNames propriedade é definida, o DetailsView controle cria automaticamente um DataKey objeto que representa o campo de chave ou campos para o registro atual. Use a DataKey propriedade para obter esse DataKey objeto. Essa propriedade é comumente usada para obter as chaves e seus valores correspondentes para os campos especificados na DataKeyNames propriedade.
Observação
Como atalho, você também pode usar a SelectedValue propriedade para determinar o valor do primeiro campo de chave listado na DataKeyNames propriedade.