Why if part not executed in laravel 5 controller method? - laravel-5

Question

public function index1()
{
$g = Request::Input('grade');
$s = Request::Input('subject');
if(strcmp($g,'Select A Grade')==0 || strcmp($s,'Select A Subject')==0) {
if (strcmp($s, 'Select A Subject') == 0) {
// Session::flash('msg', 'Please select the Subject.');
return redirect()->back()->withInput();
} else if (strcmp($g, 'Select A Grade') == 0) {
// Session::flash('msg', 'Please select the Grade.');
return redirect()->back()->withInput();
}
}
else{
$u = DB::table('upldtbls')->where('grade',$g)->where('subject',$s)->get();
return view('2Eng',compact('u'));
}
}
Above is the controller method. Main else part executed correctly. But main if part not executed as I wanted. In main if condition I want to stay on the same page if drop box values are equal to that which means when they haven't select an option from drop box. Can any one figure out this mess?
{!! Form::select('Select A Grade', array('' => 'Select A Grade','2' => '2', '3' => '3','4' => '4'), 'Select A Grade', ['class' => 'form-control'])
{!! Form::select('Select A Subject', array('' => 'Select A Subject','English' => 'English', 'Mathematics' => 'Mathematics','Environmental Studies' => 'Environmental Studies'), 'Select A Subject', ['class' => 'form-control']) !!}

Answer 1

The if part is probably not being executed because the condition is not being met. Check that $g or $s is equal to 0 as per you check. If you are simply trying to see if these Input parameters are empty / blank, amend your if statement to:
if(!$g || !$s){
...
}
Also, you should really use Request::Input instead of $_GET, but you need to fix it to one of the below:
# Laravel 5.1.x or earlier
$g = Request::Input('grade');
$s = Request::Input('subject');
or
# Laravel 5.2.x or later
$g = $request->input('grade');
$s = $request->input('subject');
UPDATE
The issue is with your select boxes. You have incorrectly named them, and you would have noticed this if you carried out some basic debugging. Update them as follows:
{!! Form::select('grade', array('' => 'Select A Grade','2' => '2', '3' => '3','4' => '4'), null, ['class' => 'form-control'])
{!! Form::select('subject', array('' => 'Select A Subject','English' => 'English', 'Mathematics' => 'Mathematics','Environmental Studies' => 'Environmental Studies'), null, ['class' => 'form-control']) !!}
i.e. the first parameter should be the name of the field, which gets passed to $_GET. After updating the form, please update the if statement to my suggestion above.