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HomeBackend DevelopmentPHP TutorialPHP中数组的定义方式

<code>$array1 = array();
$array2 = [];</code>

上述两者数组的定义方式有何区别

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<code>$array1 = array();
$array2 = [];</code>

上述两者数组的定义方式有何区别

$array1 = array();
这种写法是使用了构造函数也就是内置函数 array()
$array2 = [];
这种写法通常我们称之为数组的字面量,但仅在5.4之后支持
这两没有太大区别,而且很多语言都有此类的定义方法,如javascript

没区别,版本如果是5.4之后的,推荐使用[]方式申明数组

没有区别,第一种方式可以在5.3及之前的版本使用,兼容性好一些

没有区别,但是个人选择前者

[]方式更简洁,但只能是5.4之后,用之前要确认生产服务器的php版本,不然会蛋疼的

5.4之后支持[]

没有区别,[]是5.4加入的简化写法,可以说是语法糖

首先5.4之后你可以用[],其次建议用array(),既然你会提这个问题,那别人也会有跟你一样的疑惑,个人建议不要用一些简洁,"花俏"的写法,因为别人在看代码时,难免会有疑惑.

第一种是标准写法,
第二种和json JavaScript格式差不多,应该是为了别人的时候方便

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