DetailsView.DataKey Property

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Gets a DataKey object that represents the primary key of the displayed record.

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

Property Value

DataKey

A DataKey that represents the primary key of the displayed record.

Attributes: BrowsableAttribute

Examples

The following code example demonstrates how to use the DataKey property to determine the key field and corresponding value for the current record.


<%@ 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>

Remarks

When the DataKeyNames property is set, the DetailsView control automatically creates a DataKey object that represents the key field or fields for the current record. Use the DataKey property to get this DataKey object. This property is commonly used to obtain the keys and their corresponding values for the fields specified in the DataKeyNames property.

Note

As a shortcut, you can also use the SelectedValue property to determine the value of the first key field listed in the DataKeyNames property.

Applies to

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