SqlRoleProvider.IsUserInRole(String, String) Method     
Definition
Important
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Gets a value indicating whether the specified user is in the specified role.
public:
 override bool IsUserInRole(System::String ^ username, System::String ^ roleName);public override bool IsUserInRole(string username, string roleName);override this.IsUserInRole : string * string -> boolPublic Overrides Function IsUserInRole (username As String, roleName As String) As BooleanParameters
- username
- String
The user name to search for.
- roleName
- String
The role to search in.
Returns
true if the specified user name is in the specified role; otherwise, false.
Exceptions
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.
An unknown error occurred while communicating with the database.
Examples
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>
<%@ 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
Dim users As MembershipUserCollection
Public Sub Page_Load()
  Msg.Text = ""
  Try
    If Not Roles.IsUserInRole(User.Identity.Name, "Administrators") Then
      Msg.Text = "You are not authorized to view user roles."
      UsersListBox.Visible = False
      Return
    End If
  Catch e As HttpException
    Msg.Text = "There is no current logged on user. Role membership cannot be verified."
    Return
  End Try
  If Not IsPostBack Then
    ' Bind users to ListBox.
    users = Membership.GetAllUsers()
    UsersListBox.DataSource = users
    UsersListBox.DataBind()
  End If
  ' If a user is selected, show the roles for the selected user.
  If Not UsersListBox.SelectedItem Is Nothing Then
    ' Bind roles to GridView.
    rolesArray = Roles.GetRolesForUser(UsersListBox.SelectedItem.Value)
    UserRolesGrid.DataSource = rolesArray
    UserRolesGrid.DataBind()
    UserRolesGrid.Columns(0).HeaderText = "Roles for " & UsersListBox.SelectedItem.Value
  End If
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: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>
Remarks
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).