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These 5 bad habits in PHP programming must be changed PHP is the best language in the world!

Test whether the array is empty before looping?

$items = [];// ...if (count($items) > 0) {    foreach ($items as $item) {        // process on $item ...
    }}复制代码

foreachLoop or array function (array_*)can handle empty arrays.

• No need to test first
• You can reduce one level of indentation

$items = [];// ...foreach ($items as $item) {    // process on $item ...}复制代码

Encapsulate all the contents of the method in an if statement

function foo(User $user) {    if (!$user->isDisafunction foo(User $user) {    if (!$user->isDisabled()) {        // ...
        // long process
        // ...
    }
}bled()) {        // ...
        // long process
        // ...
    }
}复制代码

This is not PHP specific, but I see it all the time. You can reduce the indentation level of minimalist code by returning early! All "useful" bodies of the function are now at the first indentation level

function foo(User $user) {    if ($user->isDisabled()) {        return;
    }    // ...
    // long process
    // ...}复制代码

Multiple calls to issetMethod

$a = null;
$b = null;
$c = null;// ...if (!isset($a) || !isset($b) || !isset($c)) {    throw new Exception("undefined variable");
}// orif (isset($a) && isset($b) && isset($c) {    // process with $a, $b et $c}// or $items = [];//...if (isset($items['user']) && isset($items['user']['id']) {    // process with $items['user']['id']}复制代码

We often need to check if a variable has been defined ( instead of null). In PHP we can do this using isset function. And the function can accept multiple parameters at a time!

$a = null;
$b = null;
$c = null;// ...if (!isset($a, $b, $c)) {    throw new Exception("undefined variable");
}// orif (isset($a, $b, $c)) {    // process with $a, $b et $c}// or $items = [];//...if (isset($items['user'], $items['user']['id'])) {    // process with $items['user']['id']}复制代码

echo method combined with sprintf

$name = "John Doe";echo sprintf('Bonjour %s', $name);复制代码

This code may be smiling, but I happened to write it a while ago. And I still see a lot of it! Instead of combining echo and sprintf, we can simply use the printf method.

$name = "John Doe";
printf('Bonjour %s', $name);复制代码

Checking the existence of a key in an array by combining two methods

$items = [    'one_key' => 'John',    'search_key' => 'Jane',
];if (in_array('search_key', array_keys($items))) {    // process}复制代码

The last mistake I see often is using a combination of in_array and array_keys. All of these can be replaced using array_key_exists.

$items = [    'one_key' => 'John',    'search_key' => 'Jane',
];if (array_key_exists('search_key', $items)) {    // process}复制代码

We can also use isset to check whether the value is null.

if (isset($items['search_key'])) {    // process}复制代码

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