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javascriptjavascript-objects

Reverse order of object values while maintaining order of keys

I have the following object...

{0: "#000000", 1: "#FFFFFF", 0.292: "#ff0000", 0.7: "#3498db"}

How can reverse the order of the hex values respective to their keys? This is what I want to achieve...

{0: "#FFFFFF", 0.292: "#3498db", 0.7: "#ff0000", 1: "#000000"}
Solution 
  • function reverseValues(original) {
  // put into a combination array
  var combined = [];
  for (var key in original) {
    // note: keys are always strings! So use +key to convert to a number for sorting
    combined.push({key: +key, val: original[key]});
  }

  // sort it by the key value
  combined.sort((a, b) => a.key - b.key);

  // Create the result
  var result = {};
  var combinedMax = combined.length - 1;
  combined.forEach((kv, i) => result[kv.key] = combined[combinedMax - i].val);
  return result;
}

var testVal = {0: "#000000", 1: "#FFFFFF", 0.292: "#ff0000", 0.7: "#3498db"};
console.dir(reverseValues(testVal));