访问 Typescript 中的 object 内的数组

Question

I am having an Array called Entites, in which i have an object that contains "title", "category" and an array feedbacks.

createEntity(title:string,catgory:category){
        if(this.m_role=="Admin"){
          var obj ={"title":title,
                    "category":catgory,
                    feedbacks:['hello']
        };
         this.Entites.push(obj);
        }else{
            console.log("You need to be an Admin to create Entity.");
        }
    }

What i want to do is i want to push into this feedback array. I am trying this

//writeFeedback[User]
    writeFeedback(feed:string,titleOfEntity:string){
        if(this.m_role=="User"){
            const to_edit=this.Entites.indexOf({"title":titleOfEntity});
            this.Entites[to_edit].feedbacks.push('Added Feedback');
        }
    }

But this doesn't work. On logging 'to_edit' I get -1. What am I doing wrong? I get this error message on the compilation

Property 'feedbacks' does not exist on type 'object'

Answer 1

You can use Array.prototype.map for that:

  writeFeedback(feed: string, titleOfEntity: string) {
    if (this.m_role == 'User') {
      this.Entites = this.Entites.map((ent) =>
        ent.title === titleOfEntity
          ? { ...ent, feedbacks: [...ent.feedbacks, 'Added Feedback'] }
          : ent
      );
    }
  }

Update:

Property 'feedbacks' does not exist on type 'object'

If you have an interface for entities then add feedbacks to that or create a new interface.

interface Entity {
    title: string;
    category: Category;
    feedbacks: string[];
}

// inside the class
Entities: Entity[]

Answer 2

To obtain a matching item within an array use map() and indexOf(). Then check the index before updating the indexed array item:

const to_edit=this.Entites.map(e => 
   e['title']).indexOf(titleOfEntity);

if (to_edit > -1)        
    this.Entites[to_edit].feedbacks.push('Added Feedback');