Laravel API - 当状态字段为空时显示所有地区

Question

下面给出的是我的代码，用于显示输入状态的特定区域。但是在这段代码本身中，如果状态字段为空，我想显示数据库中的所有地区。如何修改我的代码以获得这样的输出。所以，我想要的 API 可以在调用 api 时返回所有地区。并且只有在输入状态字段时，它才会显示特定于它的特定地区。帮助我提出你的建议。

public function state_lookup(Request $request)
{
     $validator = Validator::make
    ($request->all(),
        [
            'state'     => 'string',
        ]
    );

    if ($validator->fails()) {
        return response()->json(
            [$validator->errors()],
            422
        );
    }

    if(empty($request->state)){
        $dist=PersonalDetails::get(['district']);
        return response()->json($dist);
    }

    $data = PersonalDetails::where('state',$request->state)->get(['district']);
 // dd($data);
    if(count($data)){

        return response()->json(['message'=>'success','data'=>$data]);
    }
    else{
        return response()->json(['message'=>'Invalid State']);
    }
}

在失败的情况下，我得到如下 json 结果

    {
    "message": "success",
    "data": []
}

它显示“成功”而不是“无效状态”

Answer 1

试试这个，

//In your controller
$request->validate([
   'state' => 'string'
]);

// $request->validate it self return error messages you have to display 
// for an example (write below code in your blade file)
@error('state')
  <div class="alert alert-danger">{{ $message }}</div>
@enderror

// write below code in your controller file
 $details = PersonalDetails::select('district');

 $details->where(function($query) use($request) {
       if (isset($request->state) && $request->state != '') {
          $query->where('state', $request->state);
       }
       // do what you want to filter in your query like above
 });

 $data = $details->get();

Answer 2

您可以使用when

$data = PersonalDetails::when(!empty($request->state),function ($query)use($request){
        $query->where('state',$request->state);
    })->get(['district']);

或

   $data = PersonalDetails::where(function ($query)use($request){
        if(isset($request)&&!empty($request)){
            $query->where('state',$request->state);
        }
       
    })->get(['district']);

为了避免0键响应变化如下

if(count($data)){

   return response()->json(['message'=>'success','data'=>$data]);
}