php 三元运算符的使用介绍,php运算符
php 三元运算符的使用介绍,php运算符
我们写PHP的时候,可能if{...}else{...}用的是最多的,但是有时候,我们可以用C里边的三元运算,可以使代码精减很多!本文章讲述我在php开发中使用三元运算的一些技巧和需要注意的地方。需要的码农可以参考一下。
今天一个网友在群里发了个题目不难,但是可能会错
<span>echo</span> <span>$a</span> == 1 ? 'one' : <span>$a</span> == 2 ? 'two' : <span>$a</span> == 3 ? 'three' : <span>$a</span> == 4 ? 'foura' : 'other'<span>; </span><span>echo</span> "\n";
输出结果是:
结果是:four
一开始想不明白,按照我的理解,应该是这样的逻辑:
echo ($a == 1 ? 'one' :
( $a == 2 ? 'two' :
( $a == 3 ? 'three' :
($a == 4 ? 'four' : 'other'))));
输出为:two
后来在kevinG(qq:48474)的指教下,参看php手册,终于明白了php的三元符的解释是从左到右的,

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