第一篇博文：PHP函数原型中的可选参数写法为何这么写
第一篇博文：PHP函数原型中的可选参数写法为什么这么写？
第一篇，算是开始吧。简单写点儿东西。
刚开始学PHP，在看PHP Manual时遇到一个问题：含可选参数的函数原型中，可选参数的写法看不懂。
例如explode函数
<span style="font-size: 14px;">array explode ( string $delimiter , string $string [, int $limit ] )</span>
可选参数都用“[方括号]”括起来，那么第三个参数$limit为可选参数。
可是为什么不这么写呢：
<span style="font-size: 14px;">array explode ( string $delimiter , string $string ,[int $limit ] )</span>
实在是无法理解这个逗号的位置。
- 1楼DeanChopper
- 可选指的是[]内的东西可有可无而不是参数，所以按你的方式无论有没有最后的参数第二个参数后面都有一个,显然这是不行的
- Re: yangtoude
- @DeanChopper，明白了，谢谢！
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