Sorting an array of objects specifying sort criteria as a string

Question

I would like to have a function to sort an array of objects by getting a string as input that include the name of the property and sort direction. I need something like this :

var myArray = [{name:"A", age: 30}, {name:"B", age:20}, {name:"C", age:20}];

var strSort = "age asc, name desc";

var sortedArray = customSortFuntion(myArray,strSort);
//sortedArray == [{name:"C", age:20}, {name:"B", age:20},{name:"A", age: 30}]

function customSortFuntion(myArray,strSort)
{
 //return sorted by age asc and sorted by name desc etc..??
}

Answer 1

This solution requires Array.prototype.map ("shim"-able) to present:

function customSortFunction(myArray,strSort){
    var sorts=strSort.split(",").map(function(v,i){
        var o=v.match(/\s(asc|desc)$/i);
        if(o){
            return {"prop":v.replace(/\s(asc|desc)$/i,"").replace(/^\s+|\s+$/,""),"order":o[1].toLowerCase()};
        }else{
            return {"prop":v,"order":"asc"};
        }
    });
    myArray.sort(function(a,b){
        var av,bv;
        for(var i=0;i<sorts.length;i++){
            av=a[sorts[i]["prop"]] || 0;
            bv=b[sorts[i]["prop"]] || 0;
            if(sorts[i]["order"]=="asc"){
                if(av>bv){
                    return 1;
                }else if(bv>av){
                    return -1;
                }
            }else{
                if(av>bv){
                    return -1;
                }else if(bv>av){
                    return 1;
                }
            }
        }
        return 0;
    });
    return myArray;
}

Online demo

Given this array:

[
    {name:"Z", age: 6}, 
    {name:"Z", age: 19}, 
    {name:"A", age: 30}, 
    {name:"B", age: 20}, 
    {name:"C", age: 20}, 
    {name:"A", age: 31}
]

and sort order name asc, age desc,

gives this output:

[ { name: 'A', age: 31 },
  { name: 'A', age: 30 },
  { name: 'B', age: 20 },
  { name: 'C', age: 20 },
  { name: 'Z', age: 19 },
  { name: 'Z', age: 6 } ]