js 把數組對象按照某個屬性進行排序

var arr=[{a:1},{a:3},{a:2}];
function objSort(prop){
				 return function (obj1, obj2) {
        var val1 = obj1[prop];
        var val2 = obj2[prop];
        if (!isNaN(Number(val1)) && !isNaN(Number(val2))) {
            val1 = Number(val1);
            val2 = Number(val2);
        }
        if (val1 < val2) {
            return -1;
        } else if (val1 > val2) {
            return 1;
        } else {
            return 0;
        }            
    }
}

arr.sort(objSort('a'));    //var arr=[{a:1},{a:2},{a:3}];
(上面代碼返回的升序，如果想返回降序把“return -1“ 和 “return 1” 跳轉一下位置)