将唯一对象添加到数组 reactjs

Question

i have problem here, when i click into one element 2 times it will add 2 time into my array, i dont know how to add unique element into array, can u guys help me? Thank you guys

 const handleClick = (
    id: number,
    name: string | null,
    avatar: string | null
  ) => {
    setListChoose((prevState: any) =>
      [...prevState].concat({ id, name, avatar })
    );
  };

Answer 1

You can check that whether that contact exists in array or not. If not then append in list else don't.

const handleClick = (
    id: number,
    name: string | null,
    avatar: string | null
  ) => {
    let list = Array.from(listChoose); //assuming that list name is listChoose.
    if(list.find(l => l.id === id) === undefined){
       setListChoose((prevState: any) =>
          [...prevState].concat({ id, name, avatar })
       );
    }
  };