Change order of key value pairs in array by other array in JavaScript

Question

I want to change the order of the key value pairs in an array (analyzeTableData) by another array (analyzeTableHeader).

const analyzeTableHeader = ["TermA", "TermC", "TermB"];
const analyzeTableData = [
{
   "TermA": "test1",
   "TermB": "test2",
   "TermC": "test3"
}, {
   "TermA": "test1a",
   "TermB": "test2a",
   "TermC": "test3a"
}];

I've tried to do it with sort and indexOf but It doesn't work.

analyzeTableData.sort(function (a, b) {
   return analyzeTableHeader.indexOf(a) - analyzeTableHeader.indexOf(b);
});

Expected Output:

const analyzeTableData = [
{
   "TermA": "test1",
   "TermC": "test3",
   "TermB": "test2"

}, {
   "TermA": "test1a",
   "TermC": "test3a",
   "TermB": "test2a"
}];

Thank you for your hints

Can you show expected output? Im guessing Array.map would be useful. — JBallin, Apr 25 '23 at 19:36
Are you aware that relying on object key order has some caveats? Are you open to other data structures? https://stackoverflow.com/questions/5525795/does-javascript-guarantee-object-property-order — JBallin, Apr 25 '23 at 19:40
You can't change the order of properties in an object. See https://stackoverflow.com/questions/5525795/does-javascript-guarantee-object-property-order — Barmar, Apr 25 '23 at 19:40
`analyzeTableData.sort()` sorts the objects, not the properties in the array elements. — Barmar, Apr 25 '23 at 19:41

gdarcan · Answer 1 · 2023-04-25T19:46:29.483

Order of keys in an object (items of analyzeTableData) doesn't make difference. As I understand (correct me please if I'm wrong), you'll print them out somewhere as the order of analyzeTableHeader. So you can use analyzeTableData as follows:

analyzeTableData.forEach(row => {
  analyzeTableHeader.forEach(col => {
    console.log(col, row[col] );
  });
});

and output will be ordered as below;

finally, you can make new Data from above code

const newAnalyzeTableData = [];
analyzeTableData.forEach(row => {
  let newRow = {};
  analyzeTableHeader.forEach(col => {
    newRow[col] = row[col];
  });
  newAnalyzeTableData.push(newRow);
});

console.log(JSON.stringify(newAnalyzeTableData, null, 4));

Change order of key value pairs in array by other array in JavaScript

1 Answers1