php ucwords 单词的首字母大写

$foo = 'hello world!';
$foo = ucwords($foo); // Hello World!

$bar = 'HELLO WORLD!';
$bar = ucwords($bar); // HELLO WORLD!
$bar = ucwords(strtolower($bar)); // Hello World!

 

$foo = 'hello|world!';
$bar = ucwords($foo); // Hello|world!

$baz = ucwords($foo, "|"); // Hello|World!