[PHP知识库]开发中可以简约代码，提高效率的php函数或预定义常量[持续更新]

开发中可以简约代码，提高效率的php函数或预定义常量[持续更新]

PHP_EOL — 当前平台中对于换行符的定义。

echo PHP_EOL;
//windows平台相当于    echo "\r\n";
//unix\linux平台相当于    echo "\n";
//mac平台相当于    echo "\r";

sprintf() — 把百分号（%）符号替换成一个作为参数进行传递的变量

$number = 2;
$str = "Shanghai";
$txt = sprintf("There are %u million cars in %s.",$number,$str);
echo $txt;
//运行的结果为 There are 2 million cars in Shanghai.

compact() —创建一个包含变量名和它们的值的数组：

$firstname = "Peter";
$lastname = "Griffin";
$age = "41";
$result = compact("firstname", "lastname", "age");
print_r($result);
//运行结果如下：
Array
(
    [firstname] => Peter
    [lastname] => Griffin
    [age] => 41
)

list() —用于在一次操作中给一组变量赋值。

$my_array = array("Dog","Cat","Horse");
list($a, $b, $c) = $my_array;
echo "I have several animals, a $a, a $b and a $c.";
//结果
I have several animals, a Dog, a Cat and a Horse.