updating image hasfile condition - laravel

Question

Now i'm trying to update an image but in method update it keeps skip the hasfile condition
public function update(Request $request, $id)
{
$slider = Slider::find($id);
$slider->header = $request->header;
$slider->paragraph=$request->paragraph;
if($request->hasFile('image')){
return 'a';
// $image=$request->file('image');
// $filename=time(). '.' .$image->getClientOriginalExtension();
// $location=public_path('images/' . $filename);
// Image::make($image)->save($location);
// $oldFilename=$slider->image;
// $slider->image=$filename;
// File::delete(public_path('images/'. $oldFilename));
}else{
return 'whatever';
}
}
and here's my view
<form class="form-horizontal" action="{{ route('slider.update',$slider->id) }}" method="post" enctype="multipart/form-data">
{{ csrf_field() }}
{{method_field('PATCH')}}
<div class="row">
<div class="col-lg-12">
<div class="ibox float-e-margins">
<div class="ibox-title back-change">
<h5>الغلاف </h5>
</div>
<div class="ibox-content">
<div class="row">
<div class="col-md-6">
<div class="image-crop">
<img src="{{asset('images/'.$slider->image)}}">
</div>
</div>
<div class="col-md-6">
<div class="btn-group">
<label title="Upload image file" for="inputImage" class="btn btn-primary">
<input type="file" name="image" id="inputImage" class="hide">
Upload new image
</label>
</div>
</div>
<div class="form-group">
<div class="col-lg-offset-2 col-lg-10">
<button class="btn btn-primary pull-right" type="submit"> حفظ التغيرات</button>
</div>
</div>
</div>
</div>
</div>
Why can I not get to the condition?
The form is okay and the name of the input is okay, but it still returns to else.