怎样在类里面创建DOMDocument对象变量?该如何处理 -PHP Tutorial-php.cn

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怎样在类里面创建DOMDocument对象变量?该如何处理

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Jun 13, 2016 pm 01:42 PM

domdocumentmusicnew

怎样在类里面创建DOMDocument对象变量?
class XXX
{
private $_music = new DOMDocument();
}

这样就报错了，
然而不在类里面直接这样的话
$_music = new DOMDocument();

就不报错，请问在类里面要怎样才能创建这样的对象变量?

------解决方案--------------------
语法错误而已，摘自手册属性中的变量可以初始化，但是初始化的值必须是常数，这里的常数是指php脚本在编译阶段时就为常数，而不是在编译阶段之后在运行阶段运算出的常数。
一般都是放到 __construct()构造函数里赋值，而外面只是声明。

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