php中利用array_filter过滤数组为空值
在我们开发过程中,判断数组为空时你会想到什么方法呢?首先想到的应该是empty函数,不过直接用empty函数判断为空是不对的,因为当这个值是多维数的时候,empty结果是有值的。
其实我们可以利用array_filter函数轻松去掉多维空值,而数组的下标没有改变,下面是举例用法:
array_filter() 函数用回调函数过滤数组中的元素,如果自定义过滤函数返回 true,则被操作的数组的当前值就会被包含在返回的结果数组中, 并将结果组成一个新的数组。如果原数组是一个关联数组,键名保持不变。
代码如下 | 复制代码 |
上面代码输出结果为: Array |
这样就把为空或者null或者false的值排除掉
上面我们再进行优化
代码如下 | 复制代码 |
function delEmpty($v) { if ($v==="" || $v==="php") //当数组中存在空值和php值时,换回false,也就是去掉该数组中的空值和php值 { return false; } return true; } $a=array(0=>"pig",1=>"Cat",2=>"",3=>"php"); print_r(array_filter($a,"delEmpty")); |

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