Comparing two objects taken arrays deleted and the new array

//原数据
let oldArr = [{faqId: 1, faqName: null}, {faqId: 2, faqName: null}, {faqId: 3, faqName: null}, {faqId: 4, faqName: null},{faqId: 5, faqName: null}]

// delete the new data over the data 
the let newArr = [ {faqId: 2, faqName: null}, {faqId:. 4, faqName: null}, {faqId:. 6, faqName: null} , {faqId:. 8, faqName : null} ]

let NewIdArr = newArr.map((e) => e.faqId); 
Let oldIdArr oldArr.map (= (e) => e.faqId); 

          let addIdArr = NewIdArr.filter ((i) => {
            return oldIdArr.indexOf(i) === -1;
          }); // add the last data faqId
          Let delIdArr = oldIdArr.filter ((i) => {
            return NewIdArr.indexOf(i) === -1;
          }); // finally deleted data faqId
          = addFaqList the let []; 
　　　　　　// Returns an array of the object based on the id add, delete empathy
          this.rowSelection.selectedRows.forEach((e) => {
            addIdArr.forEach((ele) => {
              if (e.faqId === ele) {
                addFaqList.push(e);
              }
            });
          });