将无限数量的参数传递给sort（）函数

Question

The task at hand is to create a function that takes an unlimited number of arguments to sort the array by.

For instance:

var data = [['John','London',35],
            ['Ricky','Kuala Lumpur',38],
            ['Ivan','Moscow,29]];

function arrangeOrder(a,b) {
 //Sort by field [0]
 if (a[0] > b[0]) return 1;
 if (a[0] < b[0]) return -1;

 //Sort by field [1]
 if (a[1] > b[1]) return 1;
 if (a[1] < b[1]) return -1;

 //Sort by field [2]
 if (a[2] > b[2]) return 1;
 if (a[2] < b[2]) return -1;
}

data.sort(arrangeOrder);

Works perfectly! However, the data content and the number of fields can change, as well as the fields and the number of fields that the data need to be sorted by. So what I need is to be able to specify the function is this way:

data.sort(arrangeOrder(1,3,6,9,2));

I found the way to add ONE parameter:

function propComparator(prop) {
  return function(a,b){
    return a[prop] - b[prop];
  }
}
data.sort(propComparator(prop));

As well as the way to process undifened number of arguments for the function using well arguments object:

function foo() {
  for (var i = 0; i < arguments.length; i++) {
    console.log(arguments[i]);
  }
}

But I can't seem to make this work in combination. It should be possible, but I guess I just lack the skill.

NOTE: ES6 solutions do not work in my environment, unfortunately, so I need vanilla JavaScript! Appreciate all the help I can get!

Answer 1

Use a simple for loop:

function arrangeOrder(a, b) {
  for (var i = 0; i < a.length; i++) {
    if (a[i] > b[i]) return 1;
    if (a[i] < b[i]) return -1;
  }
}

Answer 2

If you want to specify the order the indexes passed in as arguments, you can make a function that reads those arguments and returns a new function that you can pass to sort() .

 var data = [['Betty','London',35], ['Xavier','Kuala Lumpur',38], ['Alan','Moscow',35]]; function sortFunc(){ let args = arguments return function(a, b) { for (let i = 0; i < args.length; i++){ if (a[args[i]] === b[args[i]]){ continue } return a[args[i]] > b[args[i]] ? 1 : -1 } return 0 } } // Sort by age, then name, then city let f = sortFunc(2, 0, 1) data.sort(f) console.log(data) // Sort by age, then city, then name f = sortFunc(2, 1, 0) data.sort(f) console.log(data) // Also works with objects: var data = [ {name: "Mark", age:25, home: "Anchorage"}, {name: "Mark", age:15, home: "New York"}, {name: "John", age:25, home: "Aachen"}, {name: "Alice", age:15, home: "Boston"} ]; f = sortFunc("age", "home", "name") data.sort(f) console.log(data) 

Answer 3

you have already answred yourself [ I found the way to add ONE parameter ]

var data =  [['John','London',35],
            ['Ricky','Kuala Lumpur',38],
            ['Ivan','Moscow',29]];

function propComparator(prop) {
    return function(a,b){
        for (const x of prop) {
            if ( a.hasOwnProperty(prop[x]) && b.hasOwnProperty(prop[x]) ) {
                if (a[ prop[x] ] === b[ prop[x] ]) continue;
                return a[ prop[x] ] > b[ prop[x] ]?1:-1;
            } else
                continue;
        }
    }
}
var prop = [2, 0, 1, 5, 1000];
data.sort(propComparator(prop));