[Vuejs]-How i can order like a index book in Javascript?

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1👍

A simple way is the split the sections and make that into a number you can sort on..

eg. 6.2.3 -> 60203 10.5.1 -> 105010 etc.

The sort is then just a simple matter of subtract one from the other..

example…

const myarray = [
    {'secction': '6.2.3','title': 'a'},
    {'secction': '6.2.2','title': 'b'},
    {'secction': '11.3.1','title': 'bn'},
    {'secction': '10.5.1','title': 'z'},
    {'secction': '10.4.1', title: 'da'}
];


function num(a) {
  var b = a.secction.split(".");
  return b[0] * 10000 + b[1] * 100  + b[2];
}

myarray.sort((a,b) => {
  return num(a) - num(b);
});

myarray.forEach((a) => console.log(a.secction + ' -> ' + a.title));

0👍

The aim is to check first the left part of the number, then the middle part, and the right part at the end.

  • If a1 > b1, then return sth >= 1
  • If a1 < b1, return sth <= -1
  • But if a1 = a2, then check a2 and b2 (and apply this same process again, till a3 and b3)
const myarray = [
  {'secction': '6.2.3','title': 'a'},
  {'secction': '6.2.2','title': 'b'},
  {'secction': '11.3.1','title': 'bn'},
  {'secction': '10.5.1','title': 'z'},
  {'secction': '10.4.1', title: 'da'}
]

function bySecction(a, b) {
  const [a1, a2, a3] = a.secction.split('.')
  const [b1, b2, b3] = b.secction.split('.')
  
  return (a1 - b1) && (a2 - b2) && (a3 - b3)
}

myarray
  .sort(bySecction)
  .reverse()

console.log(myarray)

-1👍

You can sort like this

const myarray = [
    {'secction': '6.2.3','title': 'a'},
    {'secction': '6.2.2','title': 'b'},
    {'secction': '11.3.1','title': 'bn'},
    {'secction': '10.5.1','title': 'z'},
    {'secction': '10.4.1', title: 'da'}
];

const result = myarray.sort((a, b) => {
  const n1 = a.secction.split('.').reverse().map((n, index) => n * (10^index)).reduce((i, j) => i + j, 0);
  const n2 = b.secction.split('.').reverse().map((n, index) => n * (10^index)).reduce((i, j) => i + j, 0);
  
  return n1 - n2;
});

console.log(result);

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