析構(gòu)函數(shù)
像構(gòu)造函數(shù)一樣，您可以使用函數(shù)__destruct()定義析構(gòu)函數(shù)。您可以使用析構(gòu)函數(shù)釋放所有資源。
function __destruct() {
unset($this->price); // 銷毀
unset($this->title); // 銷毀
}
現(xiàn)在我們顯式的在析構(gòu)函數(shù)里面銷毀兩個成員變量。
class Books {
/* 成員變量 */
var $price;
var $title;
function __construct( $par1, $par2 ) {
$this->title = $par1;
$this->price = $par2;
}
/* 成員函數(shù) */
function setPrice($par){
$this->price = $par;
}
function getPrice(){
echo $this->price ."<br/>";
}
function setTitle($par){
$this->title = $par;
}
function getTitle(){
echo $this->title ." <br/>";
}
function __destruct() {
unset($this->price); // 銷毀
unset($this->title); // 銷毀
}
}
$physics = new Books( "高中物理", 10 );
$maths = new Books ( "高級化學(xué)", 15 );
$chemistry = new Books ("高等數(shù)學(xué)", 7 );
/* 獲取這些值 */
$physics->getTitle();
$chemistry->getTitle();
$maths->getTitle();
$physics->getPrice();
$chemistry->getPrice();
$maths->getPrice();
相關(guān)資料
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