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PHP去除数组中的空值

foreach( $arr as $k=>$v){       if( !$v )           unset( $arr[$k] );   }


呵呵以前都是这样写也挺美的PHP除了数组中的空值

在网上闲逛的时候,看到人有提示用array_filter,觉得很吃惊。打开手册瞅了一下,发现自己一直就守着个宝山却不知道如何使用。

array_filter函数的功能是利用回调函数来对数组进行过滤,一直都以为用回调函数才能处理,却没有发现手册下面还有一句,如果没有回调函数,那么默认就是删除数组中值为false的项目。

例程:
$entry = array(                0 => 'foo',                1 => false,                2 => -1,                3 => null,                4 => ''            );     print_r(array_filter($entry)); 


Array   (       [0] => foo       [2] => -1   )  


看来,以后还是要多看手册啊……

就象array_slice一样也是个好东西。可惜以前从来没有注意过。

建议:PHP里面最重要的两章应该就是数组操作和字符串操作,这两章里面的函数都必须要熟练,其他的就等用的时候再查吧

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