对json对象进行截取并按照某关键字进行排序

 json对象截取后三个数据，并按照时间的顺序进行倒叙排序。

var json = [{"sent_time":"08:29:09","dist":"北京"},{"sent_time":"07:28:55","dist":"上海"},{"sent_time":"08:32:09","dist":"天津"},{"sent_time":"06:29:15","dist":"广州"},{"sent_time":"06:15:24","dist":"深圳"}]

var compare = function (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;
        }            
    } 
}
if(json.length>3){
    var data = json.slice(json.length-3,json.slength).sort(compare("age"));
}else {
    var data = json.sort(compare("age"));
}
console.log(data);

---

对json数据某一字段进行排序

var s = [{
		"draggable": "true",
		"name": "58.237.119.223",
		"category": "源ip",
		"value": "1"
	}, {
		"draggable": "true",
		"name": "254.3.104.223",
		"category": "目的ip",
		"value": "3"
	}, {
		"draggable": "true",
		"name": "97.19.104.223",
		"category": "目的ip",
		"value": "2"
	}];

s.sort(function(a,b){  
        return a.value - b.value;  
    });

截取前两个

s.slice(0,2);