php Blade if(isset) 不工作 Laravel
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Blade if(isset) is not working Laravel
提问by WahidSherief
Hi I am trying to check the variable is already set or not using blade version. But the raw php is workingbut the blade version is not. Any help?
嗨，我正在尝试检查变量是否已设置或未使用刀片版本。但是原始 php 正在运行，但刀片版本不是。有什么帮助吗？
controller:
控制器：
public function viewRegistrationForm()
{
$usersType = UsersType::all();
return View::make('search')->with('usersType',$usersType);
}
view:
看法：
{{ $usersType or '' }}
it shows the error :
它显示错误：
Undefined variable: usersType (View: C:\xampp\htdocs\clubhub\app\views\search.blade.php)
未定义变量：usersType（视图：C:\xampp\htdocs\clubhub\app\views\search.blade.php）
回答by lukasgeiter
{{ $usersType or '' }}is working fine. The problem here is your foreach loop:
{{ $usersType or '' }}工作正常。这里的问题是你的 foreach 循环：
@foreach( $usersType as $type )
<input type="checkbox" class='default-checkbox'> <span>{{ $type->type }}</span>
@endforeach
I suggest you put this in an @if():
我建议你把它放在一个@if()：
@if(isset($usersType))
@foreach( $usersType as $type )
<input type="checkbox" class='default-checkbox'> <span>{{ $type->type }}</span>
@endforeach
@endif
You can also use @forelse. Simple and easy.
您也可以使用@forelse。简单易行。
@forelse ($users as $user)
<li>{{ $user->name }}</li>
@empty
<p>No users</p>
@endforelse
回答by Bhargav Kaklotara
@isset($usersType)
// $usersType is defined and is not null...
@endisset
For a detailed explanation refer documentation:
有关详细说明，请参阅文档：
In addition to the conditional directives already discussed, the
@issetand@emptydirectives may be used as convenient shortcuts for their respective PHP functions
除了已经讨论过的条件指令之外，
@isset和@empty指令可以用作各自 PHP 函数的便捷快捷方式
回答by nXu
Use 3 curly braces if you want to echo
如果要回显，请使用 3 个花括号
{{{ $usersType or '' }}}
回答by PriyankMotivaras
Use ?? , 'or' not supported in updated version.
用 ？？, 'or' 不支持更新版本。
{{ $usersType or '' }} ?
{{ $usersType ?? '' }} ?
回答by kamran
You can use the ternary operator easily:
您可以轻松使用三元运算符：
{{ $usersType ? $usersType : '' }}
回答by bad4iz
@forelse ($users as $user)
<li>{{ $user->name }}</li>
@empty
<p>No users</p>
@endforelse
回答by fred
I solved this using the optional()helper. Using the example here it would be:
我使用optional()助手解决了这个问题。使用此处的示例将是：
{{ optional($usersType) }}
{{ optional($usersType) }}
A more complicated example would be if, like me, say you are trying to access a property of a null object (ie. $users->type) in a view that is using old()helper.
一个更复杂的例子是，如果像我一样，假设您试图访问$users->type使用old()helper的视图中的空对象（即）的属性。
value="{{ old('type', optional($users)->type }}"
value="{{ old('type', optional($users)->type }}"
Important to note that the brackets go around the object variable and not the whole thing if trying to access a property of the object.
重要的是要注意，如果尝试访问对象的属性，括号会围绕对象变量而不是整个对象。
回答by Connectify_user
On Controller
在控制器上
$data = ModelName::select('name')->get()->toArray();
return view('viewtemplatename')->with('yourVariableName', $data);
On Blade file
在刀片文件上
@if(isset($yourVariableName))
//do you work here
@endif
回答by Qu?c Tu?n D??ng
Use ??instead or {{ $usersType ?? '' }}
使用??替代或{{ $usersType ?? '' }}
