Role Assignments For the Site

SPRoleAssignmentCollection webRoleAssignments =
web.RoleAssignments;

Response.Write("All role assignments in this site: " + "
");

foreach (SPRoleAssignment webRoleAssignment in webRoleAssignments)
{
Response.Write(webRoleAssignment.Member.Name + " "
+ webRoleAssignment.RoleDefinitionBindings[0].Name + " "
+ webRoleAssignment.Parent.ToString() + "
");
}