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RoleProvider.IsUserInRole(String, String) Method

  • Reference

Definition

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

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

public:
 abstract bool IsUserInRole(System::String ^ username, System::String ^ roleName);
public abstract bool IsUserInRole (string username, string roleName);
abstract member IsUserInRole : string * string -> bool
Public MustOverride Function IsUserInRole (username As String, roleName As String) As Boolean

Parameters

username
String

The user name to search for.

roleName
String

The role to search in.

Returns

Boolean

true if the specified user is in the specified role for the configured applicationName; otherwise, false.

Examples

The following code example shows a sample implementation of the IsUserInRole method.

public override bool IsUserInRole(string username, string rolename)
{
  if (username == null || username == "")
    throw new ProviderException("User name cannot be empty or null.");
  if (rolename == null || rolename == "")
    throw new ProviderException("Role name cannot be empty or null.");

  bool userIsInRole = false;

  OdbcConnection conn = new OdbcConnection(connectionString);
  OdbcCommand cmd = new OdbcCommand("SELECT COUNT(*) FROM UsersInRoles "  +
                                    " WHERE Username = ? AND Rolename = ? AND ApplicationName = ?", conn);

  cmd.Parameters.Add("@Username", OdbcType.VarChar, 255).Value = username;
  cmd.Parameters.Add("@Rolename", OdbcType.VarChar, 255).Value = rolename;
  cmd.Parameters.Add("@ApplicationName", OdbcType.VarChar, 255).Value = ApplicationName;

  try
  {
    conn.Open();

    int numRecs = (int)cmd.ExecuteScalar();

    if (numRecs > 0)
    {
      userIsInRole = true;
    }
  }
  catch (OdbcException)
  {
    // Handle exception.
  }
  finally
  {
    conn.Close();      
  }

  return userIsInRole;
}

Public Overrides Function IsUserInRole(ByVal username As String, ByVal rolename As String) As Boolean
    If username Is Nothing OrElse username = "" Then _
      Throw New ProviderException("User name cannot be empty or null.")
    If rolename Is Nothing OrElse rolename = "" Then _
      Throw New ProviderException("Role name cannot be empty or null.")

    Dim userIsInRole As Boolean = False

    Dim conn As OdbcConnection = New OdbcConnection(connectionString)
    Dim cmd As OdbcCommand = New OdbcCommand("SELECT COUNT(*) FROM UsersInRoles " & _
                                             " WHERE Username = ? AND Rolename = ? AND ApplicationName = ?", conn)

    cmd.Parameters.Add("@Username", OdbcType.VarChar, 255).Value = username
    cmd.Parameters.Add("@Rolename", OdbcType.VarChar, 255).Value = rolename
    cmd.Parameters.Add("@ApplicationName", OdbcType.VarChar, 255).Value = ApplicationName

    Try
        conn.Open()

        Dim numRecs As Integer = CType(cmd.ExecuteScalar(), Integer)

        If numRecs > 0 Then
            userIsInRole = True
        End If
    Catch e As OdbcException
        ' Handle exception.
    Finally
        conn.Close()
    End Try

    Return userIsInRole
End Function

Remarks

The IsUserInRole method is called by the IsUserInRole method of the Roles class to determine whether the current logged-on user is associated with a role from the data source for the configured ApplicationName.

If the specified user name is null or is an empty string, we recommend that your provider throw an exception.

If the specified role name is null or is an empty string, we recommend that your provider throw an exception.

Applies to

See also