need to get index of sub array of array by typescript?

Question

I have an array like

let reportData = [
    {
        ReportID: 1,
        ReportHead: 'Revenue',
        collection: 75,
        subtasks: [
            {
                ReportID: 2, ReportHead: 'Plan timeline', collection: 100, isDeleted: false,
            },
            {
                ReportID: 3, ReportHead: 'Plan budget', collection: 100, isDeleted: false,
            },
            {
                ReportID: 4, ReportHead: 'Allocate resources', collection: 100, isDeleted: false,
            },
            {
                ReportID: 5, ReportHead: 'Income complete', collection: 0, isDeleted: false,
            }
        ]
    },
    {
        ReportID: 6,
        ReportHead: 'Liabilities',
        subtasks: [
            {
                ReportID: 7, ReportHead: 'Software Specification', collection: 60, isDeleted: false,
            },
            {
                ReportID: 8, ReportHead: 'Develop prototype', collection: 100, isDeleted: false,
            },
            {
                ReportID: 9, ReportHead: 'Get approval from customer', collection: 100, isDeleted: false,
            },
        ]
    }
]

I need to get index and sub array index from this array. like a data 'ReportID: 7' this array index is 1 and the sub array index is 0 by typescript

Answer 1

Try smth like this:

const result = reportData.reduce((acc, el, idx) => {
  el.subtasks.forEach((innerEl, innerIdx) => {
    acc[innerEl.ReportID] = { arrayIdx: idx, subArrayIdx: innerIdx }
  });

  return acc;
}, {});

Result:

{
  '2': { arrayIdx: 0, subArrayIdx: 0 },
  '3': { arrayIdx: 0, subArrayIdx: 1 },
  '4': { arrayIdx: 0, subArrayIdx: 2 },
  '5': { arrayIdx: 0, subArrayIdx: 3 },
  '7': { arrayIdx: 1, subArrayIdx: 0 },
  '8': { arrayIdx: 1, subArrayIdx: 1 },
  '9': { arrayIdx: 1, subArrayIdx: 2 }
}