将一个类赋值的问题
定义了一个类
class myclass{ function test() echo "good";}$test1="myclass";$test2=new myclass();
都是把类赋值给变量,那这两种赋值方法有什么差别?
回复讨论(解决方案)
你分??出那???量就知道啦
$test1只是字符串
$test2是类的实例,是个对象
对两者gettype()可以看出区别
<?phpclass MyClassq{ const constant = 'constant value'; function showConstant() { echo self::constant . "\n"; }}echo MyClassq::constant . "\n";$classname = "MyClassq";echo $classname::constant . "\n"; // PHP 5.3.0之后$class = new MyClassq();$class->showConstant();echo $class::constant."\n"; // PHP 5.3.0之后?>
上面说的$test1 的确是字符串,echo $classname::constant . "\n";为什么能访问到类里面的内容?
复习一下“变量的变量”

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