JS查找數組中元素index

findIndex()方法返回數組中滿足提供的測試函數的第一個元素的索引。若沒有找到對應元素則返回-1。

 

值類型：   

const array1 = [5, 12, 8, 130, 44];

const isLargeNumber = (element) => element == 12;

console.log(array1.findIndex(isLargeNumber));

 

數組對象：   var index = DiaryNoList.findIndex((value) => value.diaryno == this.info.diaryno);

 

 

find()

const array1 = [5, 12, 8, 130, 44];

const found = array1.find(element => element > 10);

console.log(found);
// expected output: 12