How can I simplify this PHP? - php

Question

I have the following model functions with PHP.
I know I am repeating myself.
Is there anyway I can simplify this code?
function getTopMenus(){
$data[0] = 'root';
$this->db->where('parentid',0);
$Q = $this->db->get('menus');
if ($Q->num_rows() > 0){
foreach ($Q->result_array() as $row){
$data[$row['id']] = $row['name'];
}
}
$Q->free_result();
return $data;
}
function getheadMenus(){
$this->db->where('parentid',0);
$Q = $this->db->get('menus');
if ($Q->num_rows() > 0){
foreach ($Q->result_array() as $row){
$data[] = $row;
}
}
$Q->free_result();
return $data;
}
function getrootMenus(){
$this->db->where('parentid',0);
$Q = $this->db->get('menus');
if ($Q->num_rows() > 0){
foreach ($Q->result_array() as $row){
$data[$row['id']] = $row['name'];
}
}
$Q->free_result();
return $data;
}

Answer 1

I can see one simplification you might try, using pass-by-reference to factor things out into a function:
function prepareMenu(&$data) {
$this->db->where('parentid',0);
$Q = $this->db->get('menus');
if ($Q->num_rows() > 0){
foreach ($Q->result_array() as $row){
$data[$row['id']] = $row['name'];
}
}
$Q->free_result();
}
function getTopMenus() {
$data[0] = 'root';
prepareMenus($data);
return $data;
}
function getRootMenus() {
prepareMenus($data);
return $data;
}
There's also the possibility of using pass-by-reference and variable functions to factor out the part in the middle. May reduce duplication, but may or may not be considered 'simplifying'.
EDIT Here's what I mean. This code is untested.
function getMenus(&$data, $appendFunc) {
$this->db->where('parentid',0);
$Q = $this->db->get('menus');
if ($Q->num_rows() > 0){
foreach ($Q->result_array() as $row){
$appendFunc(&$data, $row);
}
}
$Q->free_result();
}
function appendTopMenu(&$data, $row) {
$data[$row['id']] = $row['name'];
}
function appendHeadMenu(&$data, $row) {
$data[] = $row;
}
function getTopMenus() {
$data[0] = 'root';
getMenus($data, "appendTopMenu");
return $data;
}
function getheadMenus() {
getMenus($data, "appendHeadMenu");
return $data;
}
function getrootMenus() {
getMenus($data, "appendTopMenu");
return $data;
}

Answer 2

Why not pass parameters into your function and place them in the 'where' and 'get' methods?

Answer 3

I don't know what your db and query classes look like, but i'd start improving these in the first place. Add "array fetch" and "hash fetch" functions to the query class:
class Query ...
function as_array() {
$data = array();
if($this->num_rows() > 0)
foreach ($this->result_array() as $row)
$data[] = $row;
$this->free_result();
return $data;
}
function as_hash($key = 'id') {
$data = array();
if($this->num_rows() > 0)
foreach ($this->result_array() as $row)
$data[$row[$key]] = $row;
$this->free_result();
return $data;
}
Make 'db->where()' return itself
class DB
function where(...) {
stuff
return $this;
Once you have this, your client functions become trivial:
function getTopMenus() {
$data = $this->db->where('parentid',0)->get('menus')->as_hash();
$data[0] = 'root';
return $data;
}
function getheadMenus() {
return $this->db->where('parentid',0)->get('menus')->as_array();
}
function getrootMenus() {
return $this->db->where('parentid',0)->get('menus')->as_hash();
}