Getting the lowest number in object first

Question

I'm looping over an object thats a list of terms for a student. The structure for my data looks like this:

 terms: {
  term-termId1: {
   classData: { //some class data here that im not going to list },
   class2   : { //some class data here that im not going to list },
   class3   : { //some class data here that im not going to list },
   termName: 'Spring 2018',
   gradeLevel: 9,
  },
  term-termId2: {
   classData: { //some class data here that im not going to list },
   termName: 'Summer 2018',
   gradeLevel: 9,
  },
  term-termId3: {
   classData: { //some class data here that im not going to list },
   class2   : { //some class data here that im not going to list },
   termName: 'Summer 2020',
   gradeLevel: 12,
  },
  term-termId4: {
   classData: { //some class data here that im not going to list },
   termName: 'Summer 2019',
   gradeLevel: 11,
  },
  term-termId5: {
   classData: { //some class data here that im not going to list },
   termName: 'Summer 2019',
   gradeLevel: 10,
  },
  term-termId6: {
   classData: { //some class data here that im not going to list },
   termName: 'Winter 2018',
   gradeLevel: 9,
  },
 }

Thats all the data I'll give, the entries are scattered.

I'm trying to get the lowest gradeLevel entries first so I can pass them to a function that creates table components. So for example, I want all the gradeLevel: 9 s first, then 10s, then 11s then 12s.

I just want to know a good way to do this. I can think of a few ways, like writing some if statements in the loop, but im sure it can be done a better way.

Currently I'm starting out like this:

    for (single in terms) {
      for (term in terms[single]) {
        const classes = terms[single]
        console.log(classes[term])
      }
    }

I know that loop dosn't match the data I gave, thats just how i'm getting the data on my computer. I just gave an example.

Anyway, it would be great if I could get some help figuring out the best way to get the lowest gradeLevel entries first.

I have an object of objects – reid poynter Sep 14 '20 at 17:06 — reid poynter, Sep 14 '20 at 17:06

score 1 · Accepted Answer · answered Sep 14 '20 at 17:03

1

Sort the object's values first:

const sortedValues = Object.values(data.terms).sort((a, b) => a.gradeLevel - b.gradeLevel);

Then iterate through sortedValues as needed.

answered Sep 14 '20 at 17:03

Snow

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this was perfect – reid poynter Sep 14 '20 at 17:36

score 0 · Answer 2 · answered Sep 14 '20 at 17:13

Transform your termsinto pairs of key-value, sort that pairs and transform back to object

const res = Object.fromEntries(
  Object.entries(terms).sort(
    (termA, termB) => termA[1].gradeLevel - termB[1].gradeLevel
  )
)

const terms = {
  "term-termId1": {
    termName: "Spring 2018",
    gradeLevel: 9,
  },
  "term-termId2": {
    termName: "Summer 2018",
    gradeLevel: 9,
  },
  "term-termId3": {
    termName: "Summer 2020",
    gradeLevel: 12,
  },
  "term-termId4": {
    termName: "Summer 2019",
    gradeLevel: 11,
  },
  "term-termId5": {
    termName: "Summer 2019",
    gradeLevel: 10,
  },
  "term-termId6": {
    termName: "Winter 2018",
    gradeLevel: 9,
  },
}

const res = Object.fromEntries(
  Object.entries(terms).sort(
    (termA, termB) => termA[1].gradeLevel - termB[1].gradeLevel
  )
)

console.log(res)

References

Object.prototype.entries()

Object.prototype.fromEntries()

Getting the lowest number in object first

2 Answers2