Best practice

1.  Check variable before use

<?php

$data['params'] = [1]; // or not declare

// Not Good

$result1 = isset($data['params']) && !empty($data['params']) ? $data['params'] : '';

var_dump($result1);

// Good practice

$result2 = @$data['params'] ? $data['params'] : '';

var_dump($result2);

==> 

array(1) {

  [0]=>

  int(1)

}

array(1) {

  [0]=>

  int(1)

}

2. Ternary operator (toán tử 3 ngôi)

   • Not good

      // Paginate

 $limit = $request->get('limit');

      if (!$limit) {

           $limit = 10;

           }

2. • Good

      // Paginate

 $limit = $request->get('limit') ?: 10;

3. Check isset and not empty (Kiểm tra biến trước khi xài)

   • Not Good

$data['params'] = [4];

if(isset($data["params"]) && !empty($data["params"])) {

    $result3 = $data["params"];

    var_dump($result3);

}

3. • Good

$data['params'] = [4];

if(@$data["params"]) {

    $result4 = $data["params"];

    var_dump($result4);

}

4. Redundant variable declaration (Khai báo biến dư thừa)

   • We have funtion

function query() {return null; // or anything};

4. • Not good 1

$result=query();

if($result) {

var_dump('CheckExist1 in if: ', $result+1);

}

var_dump('CheckExist1 out if: ', $result);

4. • Good 1

if($result=query()) {

var_dump('CheckExist2 in if: ', $result+1);

}

var_dump('CheckExist2 out if: ', $result);

4. • Not good 2

function sumService() {

$a = 1;

$b = 2;

//Declare but not use

$result = $a + $b;

return $result;

}

4. • Good 2

function sumService() {

$a = 1;

$b = 2;

return $a + $b;

}

5. Update