DetailsView.DataKey Eigenschaft

Referenz

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Wichtig

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Ruft ein DataKey-Objekt ab, das den Primärschlüssel des angezeigten Datensatzes darstellt.

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

Eigenschaftswert

DataKey

Ein DataKey, der den Primärschlüssel des angezeigten Datensatzes darstellt.

Attribute: BrowsableAttribute

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie Sie die DataKey Eigenschaft verwenden, um das Schlüsselfeld und den entsprechenden Wert für den aktuellen Datensatz zu bestimmen.


<%@ 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>

Hinweise

Wenn die DataKeyNames Eigenschaft festgelegt wird, erstellt das DetailsView Steuerelement automatisch ein DataKey Objekt, das das Schlüsselfeld oder die Felder für den aktuellen Datensatz darstellt. Verwenden Sie die DataKey Eigenschaft, um dieses DataKey Objekt abzurufen. Diese Eigenschaft wird häufig verwendet, um die Schlüssel und die entsprechenden Werte für die in der DataKeyNames Eigenschaft angegebenen Felder abzurufen.

Hinweis

Als Verknüpfung können Sie auch die SelectedValue Eigenschaft verwenden, um den Wert des ersten schlüsselfelds zu bestimmen, das in der DataKeyNames Eigenschaft aufgeführt ist.

Gilt für