題目描述去掉對象數組中key值相同的對象題目來源及自己的思路相關代碼let arr = [   {"weight":10,"id":1},   {"weight":20,"id":2},   {"weight":30,"id":2},   {"weight":40,"id":4},   {"weight":50,"id":5} ];你期待的結果是什么？實際看到的錯誤信息又是什么？let arr = [   {"weight":10,"id":1},   {"weight":30,"id":2},   {"weight":40,"id":4},   {"weight":50,"id":5} ];