laravel 如何访问laravel查询结果中的一列
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How to access a column in laravel query result
提问by Jaskaran Singh Puri
I'm getting an error in my controller Undefined property: Illuminate\Database\Eloquent\Collection::$created_at
我的控制器出现错误 Undefined property: Illuminate\Database\Eloquent\Collection::$created_at
How can I access a column created_atfrom a result of laravel query?
如何created_at从 Laravel 查询的结果访问列？
Controller Code:
控制器代码：
public function getDashboard() {
$posts=Post::latest('created_at')->get();
dd($posts->created_at);
// $posts->created_at=Carbon::parse($posts->created_at)->diffForHumans(Carbon::now());
return view('dashboard',compact('posts'));
}
It works with findOrFail(some_id)but not with this, why?
它适用于findOrFail(some_id)但不适用于此，为什么？
采纳答案by Alexey Mezenin
get()returns collection, so you need to iterate over it:
get()返回集合，因此您需要对其进行迭代：
foreach ($posts as $post) {
echo $post->created_at;
}
Or you could use first()to get object instead of collection. In this case this would work:
或者您可以使用first()获取对象而不是集合。在这种情况下，这将起作用：
$post = Post::latest()->first();
$post->created_at;
Also, you don't need to pass created_atto latest(), because this column is defined as default:
此外，您不需要传递created_at给latest()，因为此列已定义为默认值：
public function latest($column = 'created_at')
回答by Amit Gupta
As $postis an instance Collectionyou have to use foreachas:
作为$post一个实例，Collection您必须foreach用作：
foreach ($posts as $post) {
dd($post->created_at);
}
Or you can use firstto get first object or lastto get last object as
或者您可以使用first获取第一个对象或last获取最后一个对象作为
dd($posts->first()->created_at);
dd($posts->last()->created_at);
Update
更新
Try it as:
试试看：
foreach ($posts as $post) {
$post->diff_for_humans = $post->created_at->diffForHumans();
}
Then your can access it as:
然后你可以访问它：
foreach ($posts as $post) {
dd($post->diff_for_humans);
}
回答by meda
when you call get()you can pass an array of fields to select:
当你打电话时，get()你可以传递一个字段数组来选择：
$posts = Post::latest()->get(['created_at']);
then dump to see, what is inside with dd($post)
然后转储看看，里面有什么 dd($post)
