php 间接修改重载元素没有效果
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Indirect modification of overloaded element has no effect
提问by eComEvo
I have the following Eloquent query:
我有以下雄辩的查询：
$item = Item::where('sku', $sku)->first();
After this query comes in I'm adding a variety of elements manually such as:
在这个查询进来后，我手动添加了各种元素，例如：
$item['total'] = $item['subtotal'] + $this->currentInventory();
Statements like the above that modify the object work just fine.
像上面修改对象的语句工作得很好。
It stops working when I do the following:
当我执行以下操作时它停止工作：
$item['fields'] = [];
$fields = DB::table('item_fields')->where('item_id', $item['id'])->get();
foreach ($fields as $f) {
if (!isset($item['fields'][$f->field_group_name]))
$item['fields'][$f->field_group_name] = [];
$item['fields'][$f->field_group_name]['valid_values'] = DB::table('item_field_valid_values')->where('item_field_id', $f->item_field_id);
}
This will cause the line $item['fields'][$f->field_group_name] = [];to produce the error:
这将导致该行$item['fields'][$f->field_group_name] = [];产生错误：
Indirect modification of overloaded element of Item has no effect
How can it be that I can assign $item['fields'] = []but when I try to add an actual element to the $item['fields']array that I get this error?
我怎么能分配$item['fields'] = []但是当我尝试将实际元素添加到$item['fields']数组时出现此错误？
PHP version 5.6.0.
PHP 版本 5.6.0。
采纳答案by Jarek Tkaczyk
First off, you're missing get()in your code, so either:
首先，您get()的代码中缺少，因此：
1You are iterating over the Query\Builderinstead of the array of results, because you never executed the query. (I suppose you forgot it only here, because otherwise you would probably get trying to get property of non-object)
1您正在迭代Query\Builder而不是结果数组，因为您从未执行过查询。（我想你只是在这里忘记了它，否则你可能会得到trying to get property of non-object）
or 2one of the rows has ''or nullvalue in the field_group_namecolumn.
或2行之一在列中具有''或null值field_group_name。
That's why your code does this:
这就是为什么您的代码会这样做：
$item['fields'][NULL] = [];
and that's causing Indirect modification ...error.
这导致Indirect modification ...错误。
So add check for empty value first:
所以首先添加检查空值：
if ($f->field_group_name && ! isset($item['fields'][$f->field_group_name]))
$item['fields'][$f->field_group_name] = [];
you may need to adjust it to your needs, but you get the idea.
您可能需要根据自己的需要对其进行调整，但您明白了。
