Compare key and get neatest min key and it's value in JavaScript array of object-CodePudding

I have JS object like this

    {
        "100": {.. data },
        "200": {.. data },
        "500": {.. data },
        "1000": {.. data }
        /* so on */
    }

How to search key with any number like

if search number is between 0 to 99 then it will return false,
if search number is between 100 to 199 then it will return key 100 and its value
if 500 to 999 then return key 500 and its value
if 1000 then key as 1000 and its value

here is my code

function find(num, obj) 
{
  let keys = Object.keys(obj);
  
  result = keys.concat(Number.MAX_SAFE_INTEGER).filter(key => {
     return num <= key;
  }).shift();

  if(result === Number.MAX_SAFE_INTEGER) {
     result = keys.pop();
  }
  return result;
}


console.log( find(125, data) )

it's returning 200 instead of 100

CodePudding user response：

A simple approach here is to sort the keys in descending order, then find the first key that target larger than it.

function findNearestMinObj(obj, target) {
  const sortedKeys = Object.keys(obj).map(d => Number(d)).sort((a, b) => b - a)
  const key = sortedKeys.find(k => target >= k)
  if (key === undefined) return false
  return {
    key,
    value: obj[key]
  }
}

const data = {
  100: "one hundred",
  200: "two hundred",
  300: "three hundred",
  400: "four hundred",
  500: "five hundred",
  1000: "one thousand",
}

console.log(`123: ${JSON.stringify(findNearestMinObj(data, 123))}`)
console.log(`456: ${JSON.stringify(findNearestMinObj(data, 456))}`)
console.log(`1234: ${JSON.stringify(findNearestMinObj(data, 1234))}`)
console.log(`99: ${JSON.stringify(findNearestMinObj(data, 99))}`)
console.log(`0: ${JSON.stringify(findNearestMinObj(data, 0))}`)