.NET Framework Class Library
FormViewDataKeyNames Property

Gets or sets an array that contains the names of the key fields for the data source.

Namespace:   System.Web.UI.WebControls
Assembly:  System.Web (in System.Web.dll)
Syntax
<[%$TOPIC/wba9xy0t_en-us_VS_110_1_0_0_0_0%](GetType([%$TOPIC/wba9xy0t_en-us_VS_110_1_0_0_0_1%]))> _
Public Overridable Property DataKeyNames As [%$TOPIC/wba9xy0t_en-us_VS_110_1_0_0_0_2%]()
[[%$TOPIC/wba9xy0t_en-us_VS_110_1_0_1_0_0%](typeof([%$TOPIC/wba9xy0t_en-us_VS_110_1_0_1_0_1%]))]
public virtual [%$TOPIC/wba9xy0t_en-us_VS_110_1_0_1_0_2%][] DataKeyNames { get; set; }
[[%$TOPIC/wba9xy0t_en-us_VS_110_1_0_2_0_0%](typeof([%$TOPIC/wba9xy0t_en-us_VS_110_1_0_2_0_1%]))]
public:
virtual property array<[%$TOPIC/wba9xy0t_en-us_VS_110_1_0_2_0_2%]^>^ DataKeyNames {
	array<[%$TOPIC/wba9xy0t_en-us_VS_110_1_0_2_0_3%]^>^ get ();
	void set (array<[%$TOPIC/wba9xy0t_en-us_VS_110_1_0_2_0_4%]^>^ value);
}
[<[%$TOPIC/wba9xy0t_en-us_VS_110_1_0_3_0_0%](typeof([%$TOPIC/wba9xy0t_en-us_VS_110_1_0_3_0_1%]))>]
abstract DataKeyNames : [%$TOPIC/wba9xy0t_en-us_VS_110_1_0_3_0_2%][] with get, set
[<[%$TOPIC/wba9xy0t_en-us_VS_110_1_0_3_0_3%](typeof([%$TOPIC/wba9xy0t_en-us_VS_110_1_0_3_0_4%]))>]
override DataKeyNames : [%$TOPIC/wba9xy0t_en-us_VS_110_1_0_3_0_5%][] with get, set
<asp:[%$TOPIC/wba9xy0t_en-us_VS_110_1_0_4_0_0%] DataKeyNames="value" />

Property Value

Type: SystemString
An array that contains the names of the key fields for the data source.
Remarks

Use the DataKeyNames property to specify a comma-separated list of field names that represent the primary key of the data source. When the DataKeyNames property is set, the FormView control automatically creates a DataKey object that contains the key/value pairs of the field or fields listed in the DataKeyNames property for the current record. The DataKey object is then stored in the DataKey property.

NoteNote

You must set the DataKeyNames property for the built-in updating, deleting, and inserting features of the FormView control to work.

Examples

The following example demonstrates how to use the DataKeyNames property to specify the key field for the data source bound to the FormView control.


<%@ Page language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>FormView Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>FormView Example</h3>

      <asp:formview id="EmployeeFormView"
        datasourceid="EmployeeSource"
        allowpaging="true"
        datakeynames="EmployeeID"
        emptydatatext="No employees found."  
        runat="server">

        <rowstyle backcolor="LightGreen"
          wrap="false"/>
        <editrowstyle backcolor="LightBlue"
          wrap="false"/>

        <itemtemplate>
          <table>
            <tr>
              <td rowspan="4">
                <asp:image id="EmployeeImage"
                  imageurl='<%# Eval("PhotoPath") %>'
                  alternatetext='<%# Eval("LastName") %>' 
                  runat="server"/>
              </td>
              <td colspan="2">
                  &nbsp; 
              </td>
            </tr>
            <tr>
              <td>
                <b>Name:</b>
              </td>
              <td>
                <%# Eval("FirstName") %> <%# Eval("LastName") %>
              </td>
            </tr>
            <tr>
              <td>
                <b>Title:</b>
              </td>
              <td>
                <%# Eval("Title") %>
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:linkbutton id="Edit"
                  text="Edit"
                  commandname="Edit"
                  runat="server"/> 
              </td>
            </tr>
          </table>       
        </itemtemplate>
        <edititemtemplate>
          <table>
            <tr>
              <td rowspan="4">
                <asp:image id="EmployeeEditImage"
                  imageurl='<%# Eval("PhotoPath") %>'
                  alternatetext='<%# Eval("LastName") %>' 
                  runat="server"/>
              </td>
              <td colspan="2">
                  &nbsp; 
              </td>
            </tr>
            <tr>
              <td>
                <b>Name:</b>
              </td>
              <td>
                <asp:textbox id="FirstNameUpdateTextBox"
                  text='<%# Bind("FirstName") %>'
                  runat="server"/>
                <asp:textbox id="LastNameUpdateTextBox"
                  text='<%# Bind("LastName") %>'
                  runat="server"/>
              </td>
            </tr>
            <tr>
              <td>
                <b>Title:</b>
              </td>
              <td>
                <asp:textbox id="TitleUpdateTextBox"
                  text='<%# Bind("Title") %>'
                  runat="server"/> 
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:linkbutton id="UpdateButton"
                  text="Update"
                  commandname="Update"
                  runat="server"/>
                <asp:linkbutton id="CancelButton"
                  text="Cancel"
                  commandname="Cancel"
                  runat="server"/> 
              </td>
            </tr>
          </table>       
        </edititemtemplate> 

      </asp:formview>

      <!-- 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="EmployeeSource"
        selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
        updatecommand="Update [Employees] Set [LastName]=@LastName, [FirstName]=@FirstName, [Title]=@Title Where [EmployeeID]=@EmployeeID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>

    </form>
  </body>
</html>

<%@ Page language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>FormView Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>FormView Example</h3>

      <asp:formview id="EmployeeFormView"
        datasourceid="EmployeeSource"
        allowpaging="true"
        datakeynames="EmployeeID"
        emptydatatext="No employees found."  
        runat="server">

        <rowstyle backcolor="LightGreen"
          wrap="false"/>
        <editrowstyle backcolor="LightBlue"
          wrap="false"/>

        <itemtemplate>
          <table>
            <tr>
              <td rowspan="4">
                <asp:image id="EmployeeImage"
                  imageurl='<%# Eval("PhotoPath") %>'
                  alternatetext='<%# Eval("LastName") %>' 
                  runat="server"/>
              </td>
              <td colspan="2">
                  &nbsp; 
              </td>
            </tr>
            <tr>
              <td>
                <b>Name:</b>
              </td>
              <td>
                <%# Eval("FirstName") %> <%# Eval("LastName") %>
              </td>
            </tr>
            <tr>
              <td>
                <b>Title:</b>
              </td>
              <td>
                <%# Eval("Title") %>
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:linkbutton id="Edit"
                  text="Edit"
                  commandname="Edit"
                  runat="server"/> 
              </td>
            </tr>
          </table>       
        </itemtemplate>
        <edititemtemplate>
          <table>
            <tr>
              <td rowspan="4">
                <asp:image id="EmployeeEditImage"
                  imageurl='<%# Eval("PhotoPath") %>'
                  alternatetext='<%# Eval("LastName") %>' 
                  runat="server"/>
              </td>
              <td colspan="2">
                  &nbsp; 
              </td>
            </tr>
            <tr>
              <td>
                <b>Name:</b>
              </td>
              <td>
                <asp:textbox id="FirstNameUpdateTextBox"
                  text='<%# Bind("FirstName") %>'
                  runat="server"/>
                <asp:textbox id="LastNameUpdateTextBox"
                  text='<%# Bind("LastName") %>'
                  runat="server"/>
              </td>
            </tr>
            <tr>
              <td>
                <b>Title:</b>
              </td>
              <td>
                <asp:textbox id="TitleUpdateTextBox"
                  text='<%# Bind("Title") %>'
                  runat="server"/> 
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:linkbutton id="UpdateButton"
                  text="Update"
                  commandname="Update"
                  runat="server"/>
                <asp:linkbutton id="CancelButton"
                  text="Cancel"
                  commandname="Cancel"
                  runat="server"/> 
              </td>
            </tr>
          </table>       
        </edititemtemplate> 

      </asp:formview>

      <!-- 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="EmployeeSource"
        selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
        updatecommand="Update [Employees] Set [LastName]=@LastName, [FirstName]=@FirstName, [Title]=@Title Where [EmployeeID]=@EmployeeID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>

    </form>
  </body>
</html>
Version Information

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0
Platforms

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.