如何解决未定义的变量错误？

Question

我在$validator = $this->validator($input);定义了变量input $validator = $this->validator($input); 但这会产生未定义的变量错误。

我的控制器代码如下：

$data = $request->all();

    $validator = $this->validator($input);
    if($validator->passes()){
        $data = $this->create($input)->toArray();
        $data['token'] = str_randon[25];
        $user = User::find($data['id']);
        $user->token = $data['token'];
   `enter code here`
        $user->save();
        Mail::send('mails.confirmation', $data, function($message) use($data){
             $message->to($data['email']);
             $message->subject('regisrtation sucess and sendt mail');
        });
        return redirect(route['login'])->with('status', 'confirmation mail');
    }
   `enter code here`
    return redirect(route('login'))->with('status', $validator->error);
    `enter code here`

   }
   public function confirmation($token){
    $user = User::where('token', $token)->first();
    if(!is_null($user)){
        $user->confirmed = 1;
        $user->token = '';
        $user->save();
        return redirect(route('login'))->with('status', 'your activation is complete');
    }
    return redirect(route('login'))->with('status', 'something rong');
   }

Answer 1

您可以使用isset函数检查是否已定义Wheather变量

  if(isset($input)) {

   if($validator->passes()){
    $data = $this->create($input)->toArray();
    $data['token'] = str_randon[25];
    $user = User::find($data['id']);
    $user->token = $data['token'];
   `enter code here`
    $user->save();
    Mail::send('mails.confirmation', $data, function($message) use($data){
         $message->to($data['email']);
         $message->subject('regisrtation sucess and sendt mail');
    });
    return redirect(route['login'])->with('status', 'confirmation mail');
 }
}
 `enter code here`
return redirect(route('login'))->with('status', $validator->error);
`enter code here`

}