How to check if a variable has data in laravel blade

I generally use PHP count() :

@if(count($products) < 1)
    <div class="alert alert-warning">
        <strong>Sorry!</strong> No Product Found.
    </div>                                      
@else
    @foreach($products as $product)
        //
    @endforeach
@endif

You may also check with PHP empty() like :

 @if(!empty($products))

As you can see in the documentation :

@forelse ($users as $user)
    <li>{{ $user->name }}</li>
@empty
    <p>No users</p>
@endforelse

This code will allow you to parse all the users and display a list of them. if the $users variables is empty, then it will display a paragraph

so for you :

@forelse ($products as $product)
    //
@empty
    <div class="alert alert-warning">
        <strong>Sorry!</strong> No Product Found.
    </div>      
@endforelse

As of Laravel 5.7, You can also do this:

@empty(!$products)
   <div class="alert alert-warning">
        <strong>Sorry!</strong> No Product Found.
   </div>
@endempty

You can check like

@if(isset($products) && !empty($products))
<div class="alert alert-warning">
    <strong>Sorry!</strong> No Product Found.
</div>                                      
@else

    @foreach($products as $product)
    //
    @endforeach
@endif

What about checking length?

@if(count($products)) >= 1)
    @foreach($products as $product)
        //
    @endforeach
@else
    <div class="alert alert-warning">
        <strong>Sorry!</strong> No Product Found.
    </div>                                      
@endif

Because empty set (i mean a data stucture with zero elements) is not null at all.

php > $a = [];
php > echo is_null($a) ? 1 : 0;
// => 0

is_null Finds whether the given variable is NULL or not. but in our case we need to check whether the value in empty or not for this you can use either isset() or empty() function both work same in your case

while isset — Determine if a variable is set and is not NULL and

empty — Determine whether a variable is empty and also tell variable is set

@if(isset($products)  && !empty($products))
        @foreach($products as $product)
        //
    @endforeach                                  
@else

    <div class="alert alert-warning">
        <strong>Sorry!</strong> No Product Found.
    </div>
@endif

Do this, Check is there any records "->count() > 0" then do foreach, else alert.

@if ($products->count() > 0 )
    @foreach($products as $product)
        //enter code here
    @endforeach
@else
   <div class="alert alert-warning">
        <strong>Sorry!</strong> No Product Found.
    </div>
@endif

For me I will use logic like this

if(!$products->isEmpty()){
      return view('cart.product', compact('products'));
 }else{
   return view('pageerror', compact('products'));
 }

then you can call pageerror from your view folder to display any page that does not has data

@forelse($products as $product)
 <p>do some thing</p>
@empty
 <p>No Products</p>
@endforelse

Refer

Try this

              @forelse($products as $product)
                 //
              @empty
                <div class="alert alert-warning">
                    <strong>Sorry!</strong> No Product Found.
                </div>
              @endforelse

I found the most effective (and by far the easiest way) of accomplishing what you're trying here to be as follows.

Assumption #1: You Know The Variable Exists Within The View.

REMEMBER: an empty array will always return false.
Therefore, there is no real need to run it through a function like empty or is null. 
Comparing it to null will tell you if it exists or not.

(You could by-pass this assumption by checking to see if the variable is not equal to NULL (it's kind of bloaty if you've passed that variable through to the view, so in my opinion, I would KEEP IT SIMPLE STUPID [KISS] - if you want, you can go all fancy later when it comes to further refactoring).

ANYWAY..

I would stick to pretty similar code as you have now, maybe something like this here would be the code for your view:

@if(!$products)

    <div class="alert alert-warning">
        <strong>Sorry!</strong> No Product Found.
    </div> 

@else

    @foreach($products as $product)

        // {{ $product . “code goes here.” }}

    @endforeach

@endif

and the code for your controller would look something like this (you almost had it, remember: "perfect practice makes perfect!" - but yeah, the controller code:

public function productSearch(Request $request)
{
    // Easily obtain the name submitted by the form (I assume via the request object
    // dependency injection magic
    $name = $request->name; 

    // I would consider using the DB builder tool, as follows, as there is more docs on it
    // see: https://laravel.com/docs/5.6/queries - this will return a collection (iterable) 
    $products = DB::table(‘products’)
                ->where('name' , 'like', '%'.$name.’%’)
                ->get();

    // simply passing to the view
    return view('cart.product', compact('products'));
}

You would also need to include the Product model, DB (Laravel) and (as per usual) the request object, as follows:

// Laravel Dependencies 
use Illuminate\Support\Facades\DB;
use Illuminate\Http\Request;
// User Created Model
use App\Product;

Hopefully, this has been helpful!