php 如果一个或多个数组为空，merge_array 是否返回 null？
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merge_array returns null if one or more of arrays is empty?
提问by Joshc
I will give you quick run down of what I am doing.
我会让你快速了解我在做什么。
I am using wordpress with the advanced custom fieldsplugin. This is a php based question because these get_field()fields contain object arrays.
我正在使用带有高级自定义字段插件的wordpress 。这是一个基于 php 的问题，因为这些get_field()字段包含对象数组。
$gallery_location = get_field('gallery_location');
$gallery_studio = get_field('gallery_studio');
For example $gallery_locationwhen dumped will return this...
例如，$gallery_location当 dumped 将返回此...
array(18) {
[0]=>
array(10) {
["id"]=>
int(126)
["alt"]=>
string(0) ""
["title"]=>
string(33) "CBR1000RR STD Supersport 2014 001"
["caption"]=>
string(0) ""
["description"]=>
string(0) ""
["mime_type"]=>
string(10) "image/jpeg"
["url"]=>
string(94) "http://www.example.com/wp/wp-content/uploads/2013/10/CBR1000RR-STD-Supersport-2014-001.jpg"
["width"]=>
int(7360)
["height"]=>
int(4912)
}
... on so fourth
}
I am then using merge_array to merge both objects...
然后我使用 merge_array 来合并两个对象......
$gallery_location = get_field('gallery_location');
$gallery_studio = get_field('gallery_studio');
$downloads = array_merge( $gallery_location, $gallery_studio );
I am merging multiple arrays but if one of the arrays is empty then this is causing the merge array to return null entirely!
我正在合并多个数组，但如果其中一个数组为空，那么这将导致合并数组完全返回 null！
My question is how can I stop merge_array returning null is some of the arrays are empty?
我的问题是如何停止 merge_array 返回 null 是一些数组是空的？
Thanks in advance for any ideas.
提前感谢您的任何想法。
@zessx
@zessx
This is what I am returning...
这就是我要回来的...
$gallery_location = get_field( 'gallery_location' );
$gallery_studio = get_field( 'gallery_studio' );
$downloads = array_merge( $gallery_location, $gallery_studio );
var_dump($gallery_location);
var_dump($gallery_studio);
var_dump($downloads);
and these are the results of dumps above in same order...
这些是上面以相同顺序转储的结果......
string(0) ""
array(18) {
[0]=>
array(10) {
["id"]=>
int(126)
["alt"]=>
string(0) ""
["title"]=>
string(33) "CBR1000RR STD Supersport 2014 001"
["caption"]=>
string(0) ""
["description"]=>
string(0) ""
["mime_type"]=>
string(10) "image/jpeg"
["url"]=>
string(94) "http://www.example.com/wp/wp-content/uploads/2013/10/CBR1000RR-STD-Supersport-2014-001.jpg"
["width"]=>
int(7360)
["height"]=>
int(4912)
}
... on so fourth
}
NULL
As you can see $downloadsis still returning null, if I try and use both your solution below it does not work?
如您所见$downloads，仍然返回空值，如果我尝试使用下面的两种解决方案，它不起作用吗？
回答by zessx
array_mergeonly accepts arrays as parameters. If one of your parameters is null, it will raise an error :
array_merge只接受数组作为参数。如果您的参数之一为空，则会引发错误：
Warning: array_merge(): Argument #x is not an array...
警告：array_merge()：参数 #x 不是数组...
This error won't be raised if one of the arrays is empty. An empty array is still an array.
如果其中一个数组为空，则不会引发此错误。空数组仍然是数组。
Two options :
两种选择：
1/ Force the type to be array
1/ 强制类型为 array
$downloads = array_merge( (array)$gallery_location, (array)$gallery_studio );
2/ Check if variables are arrays
2/ 检查变量是否为数组
$downloads = array();
if(is_array($gallery_location))
$downloads = array_merge($downloads, $gallery_location);
if(is_array($gallery_studio ))
$downloads = array_merge($downloads, $gallery_studio);
回答by Константин Дмитриенко
You can use the following way for merger your arrays:
您可以使用以下方式合并您的阵列：
$c = (array)$a + (array)$b
