Laravel - 5.8 explode not working for implode - php

Question

I did save computer field like implode.
A user cannot bid on a order more than once. If the user clicks on the order again, he should be prompted with a response page noting the user of having previously bid on the order.
$order = Order::where('user_id',auth()->id())
->explode( 'computer', request('computer'));
I create multiple checkboxes and I stored implode computer
order.blade.php
<form action="{{ route('store') }}" method="post">
<input type="checkbox" name="computer[]" value="1" id="hp">
<label for="hp">HP</label>
<input type="checkbox" name="computer[]" value="2" id="dell">
<label for="dell">DELL</label>
<input type="checkbox" name="computer[]" value="3" id="asus">
<label for="asus">ASUS</label>
<input type="checkbox" name="computer[]" value="4" id="acer">
<label for="acer">ACER</label>
<input type="checkbox" name="computer[]" value="5" id="sony">
<label for="sony">Sony</label>
<input type="checkbox" name="computer[]" value="6" id="fujitsu">
<label for="fujitsu">Fujitsu</label>
<input type="checkbox" name="computer[]" value="other_barnds" id="other_barnds">
<label for="other_barnds">Other</label>
<input type="submit" class="btn btn-primary" value="Save">
</form>
OrderController.php
public function store(Request $request)
{
$this->validate(request(), [
'computer' => 'required'
]);
$order = Order::where('user_id',auth()->id())
->where('computer', request('computer'))
->exists();
$order = new Order($request->all());
$order->user_id = auth()->user()->id;
$order->description = $request->description;
$computer = implode(",", $request->computer);
$order->computer = $computer;
$order->save();
if ($order) {
alert()->error('Warning', 'You ordered already');
return redirect()->back();
}
}

Answer 1

This code won't work, because computer field is a string and $request('computer') is an array.
$order = Order::where('user_id',auth()->id())
->where('computer', request('computer'))
->exists();
Also, as my comment above, you have to pass a csrf_token to submit the form. So use #csrf in your form tag.
Try below code, I have commented every step for better understanding.
public function store(Request $request)
{
$this->validate(request(), [
'computer' => 'required'
]);
//Now fetch the user's computer record, it will give you a string.
$users_computers = Order::where('user_id',auth()->id())->get('computer');
//convert this string to array
$users_computers = explode(',',$users_computers);
//Now check if there is at least one order is common or exists
$common_orders = array_intersect($users_computers, $request['computer']);
//throw error if any orders exists already
if(count($common_orders)>0)
{
alert()->error('Warning', 'You ordered already');
return redirect()->back();
//To give which computers user have orders you can access $common_orders values.
}
$order = new Order();
$order->user_id = auth()->user()->id;
$order->description = $request->description;
$computer = implode(",", $request->computer);
$order->computer = $computer;
$order->save();
return redirect()->back();//pass here a success message if you want
}
Use eloquent relationship to fetch and store a user's orders more conveniently.