PHP 函数参数

传值

function takes_array($input) {     echo "$input[0] + $input[1] = ", $input[0]+$input[1]; }

引用

function add_some_extra(&$string) {     $string .= 'and something extra.'; } $str = 'This is a string, '; add_some_extra($str); echo $str;    // outputs 'This is a string, and something extra.'

默认值

function makecoffee ($type = "cappuccino") {     return "Making a cup of $type.\n"; } echo makecoffee (); echo makecoffee ("espresso");