php5:摘要

1.The __toString() magic method is only called when used directly with echo orprint — if any other strings or casts are present, the object id will be returned instead.

在我的测试中发现不是很正确。都可以输出__toString的值

<?phpclass Circle{public $radius; public function __toString(){return "automatic string value for circle";} public function calcArea() { return pi()*pow($this->radius,2); }}$c=new Circle();$c->radius=5;echo 'the area of the circle is'.$c->calcArea().'<br/>';echo "the value of /$c is:".$c;#echo $c;?>

2.$input_file = array_map(‘rtrim’, file(‘generic.txt’));

This line of code achieves the same effect. file() returns an array containing the lines of generic.txt; array_map() applies the function rtrim() to each element of that array, and returns the resulting “trimmed” array.