http://docs.php.net/manual/zh/function.array-keys.php
<? $x=array("1"=>"aa","2"=>"bb","3"=>"cc","4"=>"bb"); $y1=array_keys($x,bb,false); $y2=array_keys($x,bb,true); print_r($x); print_r($y1); print_r($y2);?>
函數(shù)第3個(gè)參數(shù),有什么作用?
程序?yàn)槭裁闯鲥e(cuò)了?
回復(fù)討論(解決方案)
看看這個(gè):http://baike.baidu.com/view/4068562.htm赫然看開朗
改成這樣:$y2=array_keys($x,"bb",true);?就對(duì)了
程序?yàn)槭裁闯鲥e(cuò)了?
因?yàn)?bb?不是常量,而你又沒有用引號(hào)括起
第三個(gè)參數(shù)指定是否檢查數(shù)據(jù)類型
?strict
????判斷在搜索的時(shí)候是否該使用嚴(yán)格的比較(===)。
出錯(cuò)是因?yàn)?$y1=array_keys($x, bb,false);?這里的bb沒加引號(hào),php首先會(huì)認(rèn)為它是一個(gè)常量,而你的代碼中沒有常量,所以就報(bào)錯(cuò)了。
第三個(gè)參數(shù)是根據(jù)類型返回帶有指定值的鍵名,
$x=array("1"=>"111111","2"=>"bb","3"=>"cc","4"=>"bb");
$y1=array_keys($x,111111,true);//將不再返回?cái)?shù)據(jù)(原數(shù)組里“111111”是字符串類型,而這里給的是數(shù)字類型)
報(bào)錯(cuò)是因?yàn)樽址脝我?hào)或雙引號(hào)
$y1=array_keys($x,"bb",false);
$y2=array_keys($x,"bb",true);

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