当键为动态键时，按值对对象数组进行排序

Question

I want to sort an array objects like so.

var obj = [{"UMAIR":410},
        {"ALI":2177},   
        {"JOHN":410},
        {"ANTHENY":410},
        {"FRANKLY":410},
        {"FRONTY":534},
        {"SLIM":534},
        {"ASFUND":534}];

I want to sort it with integer values of each object. I am trying to understand following code (that I have found online):

 obj.sort(function(a, b) {
    return a.price - b.price;
});

But in this code its using price property, but I dont' have any specific property here.

Answer 1

You can try the sort function...

obj.sort(function(a,b) {
   return a[Object.keys(a)[0]] - b[Object.keys(b)[0]];
});

is Equivalent to:

obj.sort(function(a,b) {
   var aValue = a[Object.keys(a)[0]];
   var bValue = b[Object.keys(b)[0]];
   if (aValue > bValue)
     return 1;
   else if (aValue < bValue)
     return -1;
   else
     return 0;
}); 

Edit, Just saw your edit, yeah you did find it. You should also search how to extract elements from json, which in your case is Object.keys,

It Returns an array with the key strings.

Since your Object contains a SINGLE key, you get from the array the first value (0) and then, you are making the subtraction of values from a to b.

a,b are entries of your array. they are objects.

In this Link you can check how sorting function works

Code from the Link i provided

function compare(a, b) {
  if (a is less than b by some ordering criterion) {
    return -1;
  }
  if (a is greater than b by the ordering criterion) {
    return 1;
  }
  // a must be equal to b
  return 0;
}