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Roles.Provider Property

  • Reference

Definition

Namespace:
System.Web.Security
Assembly:
System.Web.dll

Gets the default role provider for the application.

public:
 static property System::Web::Security::RoleProvider ^ Provider { System::Web::Security::RoleProvider ^ get(); };
public static System.Web.Security.RoleProvider Provider { get; }
static member Provider : System.Web.Security.RoleProvider
Public Shared ReadOnly Property Provider As RoleProvider

Property Value

RoleProvider

The default role provider for the application, which is exposed as a class that inherits the RoleProvider abstract class.

Exceptions

ProviderException

Role management is not enabled.

Examples

The following code example casts the default role provider as a WindowsTokenRoleProvider and checks whether the currently logged-on user is in the Administrators role before allowing the user to view roles settings for the application. For an example of a Web.config file that enables role management, see WindowsTokenRoleProvider.

<%@ Page Language="C#" %>
<%@ Import Namespace="System.Web.Security" %>
<%@ Import Namespace="System.Security.Principal" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

string[] rolesArray;

public void Page_Load()
{
  Msg.Text = "";

  WindowsPrincipal p = (WindowsPrincipal)System.Threading.Thread.CurrentPrincipal;

  if (!p.IsInRole(WindowsBuiltInRole.Administrator))
  {
    Msg.Text = "You are not authorized to view user roles.";
    return;
  }


  // Bind roles to GridView.

  try
  {
    rolesArray = Roles.GetRolesForUser(User.Identity.Name);
  }
  catch (HttpException e)
  {
    Msg.Text = "There is no current logged on user. Role membership cannot be verified.";
    return;
  }

  UserRolesGrid.DataSource = rolesArray;
  UserRolesGrid.DataBind();

  UserRolesGrid.Columns[0].HeaderText = "Roles for " + User.Identity.Name;
}

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>Sample: View User Roles</title>
</head>
<body>

<form runat="server" id="PageForm">

  <h3>View User Roles</h3>

  <asp:Label id="Msg" ForeColor="maroon" runat="server" /><br />

  <table border="0" cellspacing="4">
    <tr>
      <td valign="top"><asp:GridView runat="server" CellPadding="4" id="UserRolesGrid" 
                                     AutoGenerateColumns="false" Gridlines="None" 
                                     CellSpacing="0" >
                         <HeaderStyle BackColor="navy" ForeColor="white" />
                         <Columns>
                           <asp:TemplateField HeaderText="Roles" >
                             <ItemTemplate>
                               <%# Container.DataItem.ToString() %>
                             </ItemTemplate>
                           </asp:TemplateField>
                         </Columns>
                       </asp:GridView></td>
    </tr>
  </table>

</form>

</body>
</html>

<%@ Page Language="VB" %>
<%@ Import Namespace="System.Web.Security" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

Dim rolesArray() As String

Public Sub Page_Load()
  Msg.Text = ""

  Dim provider As WindowsTokenRoleProvider = CType(Roles.Provider, WindowsTokenRoleProvider)

  If Not provider.IsUserInRole(User.Identity.Name, _
                               System.Security.Principal.WindowsBuiltInRole.Administrator) Then
    Msg.Text = "You are not authorized to view user roles."
    Return
  End If


  ' Bind roles to GridView.

  Try
    rolesArray = Roles.GetRolesForUser(User.Identity.Name)
  Catch e As HttpException
    Msg.Text = "There is no current logged on user. Role membership cannot be verified."
    Return
  End Try

  UserRolesGrid.DataSource = rolesArray
  UserRolesGrid.DataBind()

  UserRolesGrid.Columns(0).HeaderText = "Roles for " & User.Identity.Name
End Sub

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>Sample: View User Roles</title>
</head>
<body>

<form runat="server" id="PageForm">

  <h3>View User Roles</h3>

  <asp:Label id="Msg" ForeColor="maroon" runat="server" /><br />

  <table border="0" cellspacing="4">
    <tr>
      <td valign="top"><asp:GridView runat="server" CellPadding="4" id="UserRolesGrid" 
                                     AutoGenerateColumns="false" Gridlines="None" 
                                     CellSpacing="0" >
                         <HeaderStyle BackColor="navy" ForeColor="white" />
                         <Columns>
                           <asp:TemplateField HeaderText="Roles" >
                             <ItemTemplate>
                               <%# Container.DataItem.ToString() %>
                             </ItemTemplate>
                           </asp:TemplateField>
                         </Columns>
                       </asp:GridView></td>
    </tr>
  </table>

</form>

</body>
</html>

Remarks

The Provider property enables you to directly reference the default role provider for an application. This is commonly used to access custom members of the role provider that are not part of the RoleProvider abstract class.

For example, the WindowsTokenRoleProvider class includes an overload of the IsUserInRole method that enables you to determine whether a user is in a common Windows role by using a WindowsBuiltInRole enumeration value. A reference to the WindowsTokenRoleProvider class for an application can be obtained by using the Provider property and can be cast as a WindowsTokenRoleProvider in order to refer to the IsUserInRole overload.

If multiple role providers are configured for an application, you can access different role providers using the Providers collection.

Applies to

See also