php 如何删除数组的第一个元素而不更改其键值？
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How to remove the first element of array without changing its key value?
提问by Ganesh Babu
I have an array in php
我在 php 中有一个数组
<?php
$array=array("a"=>"123","b"=>"234","c"=>"345");
array_shift($array);
//array("0"=>"234","1"=>"345");
?>
If I use this function, then key value gets changed. I want my key value to remain the same. How can I remove first element without affecting array key values. My answer should be like
如果我使用这个函数，那么键值就会改变。我希望我的键值保持不变。如何在不影响数组键值的情况下删除第一个元素。我的答案应该是
array("b"=>"234","c"=>"345");
Note:Please do not use foreach(); I want to do this by existing array functions in php
注意：请不要使用 foreach(); 我想通过 php 中现有的数组函数来做到这一点
array_splice function is working for above array. But consider the below array
array_splice 函数适用于上述数组。但考虑下面的数组
<?php
$array = Array
(
'39' => Array
(
'id' => '39',
'field_id' => '620'
),
'40' => Array
(
'id' => '40',
'field_id' => '620',
'default_value' => 'rrr',
));
array_splice($array, 0, 1);
print_r($array);
?>
It is showing answer as follows:
它显示的答案如下：
Array ( [0] => Array ( [id] => 40 [field_id] => 620 [default_value] => rrr ) )
May I know the reason?? Will array_splice() work only for single dimensional array?? Now key value is reset...
可以知道原因吗？？array_splice() 是否仅适用于一维数组？？现在键值被重置...
回答by aefxx
In case you do not know what the first item's keyis:
如果您不知道第一项key是什么：
// Make sure to reset the array's current index
reset($array);
$key = key($array);
unset($array[$key]);
回答by vikingmaster
$array=array("a"=>"123","b"=>"234","c"=>"345");
unset($array["a"]) ;
var_dump($array) ;
Also, what version of PHP do you use?
另外，您使用什么版本的PHP？
array_shiftworks fine for me with string-indexed arrays and I get the expected result.
array_shift使用字符串索引数组对我来说效果很好，我得到了预期的结果。
回答by Ganesh Babu
The solution for this question is as follows:
这个问题的解决方法如下：
<?php
unset($array[current(array_keys($array))]);
?>
It removes the first element without affecting the key values..
它删除第一个元素而不影响键值..
回答by Yatin Trivedi
<?php function array_kshift(&$array)
{
list($k) = array_keys($array);
$r = array($k=>$array[$k]);
unset($array[$k]);
return $r;
}
// test it on a simple associative array
$array=array("a"=>"123","b"=>"234","c"=>"345");
array_kshift($array);
print_r($array);
?>
