PHP Boolean注意

      今天上班真他妈的没状态，一天不知道想干么，好像还有一种莫名的紧张，烦躁，不安，说不出来的感觉，职业迷茫期不会又来了吧  ，那就上博客写篇博客，其实我是一个优秀的员工，  一只大苍蝇在我办公位飞了一天了，  上午还打算再找找PHP面向对象的知识学习学习，发现国内估计很少用php的面向对象开发，都是基于面向过程的，找资料都找不到，都是看英文的，看到一点关于PHP数据类型的文章，下面是一老外关于Boolean数据类型的特别注意性质的介绍，我还真不知道，很多情况下都是FALSE，这个跟很多语言不太一样

 

Boolean data types represent two possible states — TRUE or FALSE. Boolean values are used mainly to compare conditions for use in conditional statements. For example, PHP evaluates an expression, such as $a > $b, and the outcome is either TRUE or FALSE.

PHP considers the following values FALSE :
The string FALSE (can be upper- or lowercase)
The integer 0
The float 0.0
An empty string
The one-character string 0
The constant NULL

Any other values in a Boolean variable are considered TRUE. If you echo a Boolean variable, the value FALSE displays as a blank string; the value TRUE echoes as a 1. Functions often return a Boolean variable that you can test to see whether the function succeeded or failed.

 

PHP太灵活了，我觉得也很没有标准，学习起来特步方便