php函数中传引用参数可以设置默认值吗
像这样:
function foo(&$argument = 'bar') { ... }
这样就可以这样调用:
foo();
foo($xxx);
回复内容:
像这样:
function foo(&$argument = 'bar') { ... }
这样就可以这样调用:
foo();
foo($xxx);
可以是可以…… 不过这样有啥好处啊…… 很奇怪的用法
这个就像Java里的方法重载,是处理不固定参数个数,给参数赋默认值的方法。把Java重载需要定义多个函数,简化为只需要一个函数。
但是对于多个函数,需要注意,如果某个函数赋默认值,那么函数表里排在他后边的所有函数都要有默认值,否则参数表里的默认值没有意义,也就是说,调用的时候,只能选择 不传某个参数以及参数表其之后的所有参数。

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