Upload file using vuejs and laravel

I want to upload pdf file using vuejs and laravel but i got an error:

Call to a member function store() on array.

my vue component:

<div class="form-group">
                  <input v-model="form." type="text" name="" placeholder=""
                    class="form-control" :class="{ 'is-invalid': form.errors.has('') }">
                  <has-error :form="form" field="title"></has-error>
                </div>

<div class="form-group">

                  <input type="file" name="" placeholder="" @change="addFile"
                    class="form-input" :class="{ 'is-invalid': form.errors.has('file') }">
                </div>
data(){
        return{
form: new Form({
            title:'',
            file:''
        }),

        }
methods:{
 addFile(e){
this.form.file=e.target.files[0];
},
createFile(){

                this.form.post('/api/profpub')
}
}

My controller:

public function store(Request $request)
    {
 $pub=Profpub::create([
'titre'=>$request['titre'],
'file'=>$request->file->store(),
]);
}

via Chebli Mohamed