GridView.DataKeys 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 collection of DataKey objects that represent the data key value of each row in a GridView control.

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

Property Value

DataKeyArray

A DataKeyArray that contains the data key of each row in a GridView control.

Attributes: BrowsableAttribute

Examples

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>

Remarks

When the DataKeyNames property is set, the GridView control automatically creates a DataKey object for each row in the control. The DataKey object contains the values of the field or fields specified in the DataKeyNames property. The DataKey objects are then added to the control's DataKeys collection. Use the DataKeys property to retrieve the DataKey object for a specific data row in the GridView control.

Note

You can use the SelectedDataKey property to retrieve the DataKey object for the currently selected row. You can also use the SelectedValue property to retrieve the data key value for the currently selected row directly.

Applies to

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