SqlRoleProvider.IsUserInRole Method (String, String)

 

Gets a value indicating whether the specified user is in the specified role.

Namespace:   System.Web.Security
Assembly:  System.Web (in System.Web.dll)

public override bool IsUserInRole(
	string username,
	string roleName
)

Parameters

username
Type: System.String

The user name to search for.

roleName
Type: System.String

The role to search in.

Return Value

Type: System.Boolean

true if the specified user name is in the specified role; otherwise, false.

Exception Condition
System.ArgumentNullException

roleName is null.

-or-

username is null.

System.ArgumentException

roleName is an empty string or contains a comma.

-or-

username is contains a comma.

-or-

roleName is longer than 256 characters.

-or-

username is longer than 256 characters.

System.Configuration.Provider.ProviderException

An unknown error occurred while communicating with the database.

The IsUserInRole method is called by the Roles class and the IsInRole method of the Page.User property to determine whether a user is associated with a role in the SQL Server database specified in the ASP.NET application's configuration file (Web.config).

The following code example programmatically checks to see whether the logged-on user is in the Administrators role before allowing the user to view user roles. For an example of a Web.config file that enables role management, see SqlRoleProvider.

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

string[] rolesArray;
MembershipUserCollection users;

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

  try
  {
    if (!Roles.IsUserInRole(User.Identity.Name, "Administrators"))
    {
      Msg.Text = "You are not authorized to view user roles.";
      UsersListBox.Visible = false;
      return;
    }
  }
  catch (HttpException e)
  {
    Msg.Text = "There is no current logged on user. Role membership cannot be verified.";
    return;
  }


  if (!IsPostBack)
  {
    // Bind users to ListBox.

    users = Membership.GetAllUsers();
    UsersListBox.DataSource = users;
    UsersListBox.DataBind();
  }


  // If a user is selected, show the roles for the selected user.

  if (UsersListBox.SelectedItem != null)
  {
    // Bind roles to GridView.

    rolesArray = Roles.GetRolesForUser(UsersListBox.SelectedItem.Value);
    UserRolesGrid.DataSource = rolesArray;
    UserRolesGrid.DataBind();

    UserRolesGrid.Columns[0].HeaderText = "Roles for " + UsersListBox.SelectedItem.Value;
  }
}

</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:ListBox id="UsersListBox" DataTextField="Username" 
                                    Rows="8" AutoPostBack="true" runat="server" /></td>
      <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>

.NET Framework
Available since 2.0
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