php 需要检查laravel中的对象是否为空
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Need to check if an object is empty in laravel
提问by prgrm
I create a view by doing an eloquent query and then pass it over to Blade.
我通过做一个雄辩的查询来创建一个视图，然后将它传递给 Blade。
@if($contacts != null)
//display contacts
@else
You dont have contacts
@endif
However it always assume that $contacts has something even if the query gives me nothing.
然而，它总是假设 $contacts 有一些东西，即使查询没有给我任何东西。
I did dd($contacts)and get:
我做了dd($contacts)并得到：
Collection {#247 ▼
#items: []
}
How do I check if it is empty?
我如何检查它是否为空？
回答by gsueagle2008
If it is a Eloquent Collection as it appears to be from your example you can use the isEmpty collection helper function;
如果它是 Eloquent 集合，就像您的示例中那样，您可以使用 isEmpty 集合辅助函数；
@if(!$contacts->isEmpty())
//display contacts
@else
You dont have contacts
@endif
回答by Alexey Mezenin
There are few ways:
有几种方法：
if (!empty($contacts))
if (!contacts->isEmpty())
if (count($contacts) > 0)
if ($contacts->count() > 0)
回答by Michel
Your Eloquent query returns an array of result, so you can use count.
您的 Eloquent 查询返回一个结果数组，因此您可以使用count.
@if(count($contacts) > 0)
//Display contacts
@else
//No contacts
@endif
回答by Md. Abu Taleb
Your $contactsis empty. Bcoz Your query is unable to get data. Once your query unable to get data it's return an empty arrya. So check it
你的$contacts是空的。Bcoz 您的查询无法获取数据。一旦您的查询无法获取数据，它就会返回一个空的 arrya。所以检查一下
@if($contacts->isEmpty())
{{ 'Empty' }}
@else
{{ 'you have data' }}
@endif
回答by Dang Cong Duong
回答by Alemoh Rapheal Baja
if it is inside a controller this will help
如果它在控制器内，这将有所帮助
if(empty($query) {
//do something
}else{
//do some stuff
}
回答by Alemoh Rapheal Baja
if(count($profiles) > 0){
return redirect()->action('NameController@name');
}else{
return view('user');
}
this also works fine in a controller
这在控制器中也能正常工作
回答by Francisko Kruz Sosa
You must do the following:
您必须执行以下操作：
in the view of your " ContactController":
在您的“ ContactController”视图中：
public function index()
{
$contacts = Contact::all();
return view('page.index', compact('contacts'))
}
later on view " index.blade.php":
稍后查看“ index.blade.php”：
@if (collect($contacts)->isEmpty()) {{-- remember that $contact is your variable --}}
<p>There is no record available at this time</p>
@else
@foreach($contacts as $contact)
{{$contact->name_contact}}
@endforeach
@endif
Now, I suppose you have a model called Contact
现在，我想你有一个名为Contact的模型
