Export (0) Print
Expand All

RoleProvider.GetRolesForUser Method

Gets a list of the roles that a specified user is in for the configured applicationName.

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

Public MustOverride Function GetRolesForUser ( _
	username As String _
) As String()


Type: System.String

The user to return a list of roles for.

Return Value

Type: System.String()
A string array containing the names of all the roles that the specified user is in for the configured applicationName.

GetRolesForUser is called by the GetRolesForUser method of the Roles class to retrieve the role names that the specified user is associated with from the data source. Only the roles for the configured ApplicationName are retrieved.

If no roles exist for the specified user for the configured applicationName, we recommend that your provider return a string array with no elements.

If the specified user name is Nothing or is an empty string, we recommend that your provider throw an exception.

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

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

    Dim tmpRoleNames As String = "" 

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

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

    Dim reader As OdbcDataReader = Nothing 


        reader = cmd.ExecuteReader()

        Do While reader.Read()
            tmpRoleNames &= reader.GetString(0) & "," 
    Catch e As OdbcException
        ' Handle exception. 
        If Not reader Is Nothing Then reader.Close()
    End Try 

    If tmpRoleNames.Length > 0 Then 
        ' Remove trailing comma.
        tmpRoleNames = tmpRoleNames.Substring(0, tmpRoleNames.Length - 1)
        Return tmpRoleNames.Split(CChar(","))
    End If 

    Return New String() {}
End Function

.NET Framework

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

.NET Framework Client Profile

Supported in: 4

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.

© 2014 Microsoft