Определить маршруты
Route::get('dropdownlist','Propertcontroller@index');
Route::get('get-subcat-list','Propertcontroller@getSubcatList');
Route::get('get-subsubcat-list','Propertcontroller@getSubsubcatList');
Propertcontroller
public function index()
{
$categories= DB::table("categories")->pluck("name","categories_id");
return view('index',compact('categories'));
}
public function getSubcatList(Request $request)
{
$subcategories= DB::table("subcategories")
->where("categories_id",$request->categories_id)
->pluck("name","subcategories_id");
return response()->json($subcategories);
}
public function getSubsubcatList(Request $request)
{
$subsubcat= DB::table("subsubcat")
->where("subcategories",$request->subcategories)
->pluck("name","subcategories_id");
return response()->json($subsubcat);
}
ваш индекс
<select id="categories" name="categories_id" >
<option value="" selected disabled>Select</option>
@foreach($categories as $key => $category)
<option value="{{$key}}"> {{$category}}</option>
@endforeach
</select>
<select name="subcategories" id="subcategories"></select>
<select name="subsubcat" id="subsubcat"></select>
<script type="text/javascript">
$('#categories').change(function(){
var categoryID = $(this).val();
if(categoryID){
$.ajax({
type:"GET",
url:"{{url('get-subcategories-list')}}?categories_id="+categoryID,
success:function(res){
if(res){
$("#subcategories").empty();
$("#subcategories").append('<option>Select</option>');
$.each(res,function(key,value){
$("#subcategories").append('<option value="'+key+'">'+value+'</option>');
});
}else{
$("#subcategories").empty();
}
}
});
}else{
$("#subcategories").empty();
$("#subsubcat").empty();
}
});
$('#subcategories').on('change',function(){
var subcatID = $(this).val();
if(subcatID){
$.ajax({
type:"GET",
url:"{{url('get-subsubcat-list')}}?subcat_id="+subcatID,
success:function(res){
if(res){
$("#subsubcat").empty();
$.each(res,function(key,value){
$("#subsubcat").append('<option value="'+key+'">'+value+'</option>');
});
}else{
$("#subsubcat").empty();
}
}
});
}else{
$("#subsubcat").empty();
}
});
</script>
Еще не проверено, но, возможно, это вам немного поможет.