从字典javascript获取所有最小值

Question

I have a long dictionary with many entries {y:10, au:41, w:41, m:11, u:21, t:1, d:1} What i need is to get all keys with the lowest value in a array. I found this ( Getting key with the highest value from object ) but that doesn't work for multiple minimums(maximums)

and i need to use only core javascript.

Answer 1

The fastest and easiest is probably to get the objects keys as an array with Object.keys , and filter that array based on items having the lowest value.
One would need to find the lowest value first, then filter, here's one way to do that

 var obj = {y:10, au:41, w:41, m:11, u:21, t:1, d:1}; var keys = Object.keys(obj); var lowest = Math.min.apply(null, keys.map(function(x) { return obj[x]} )); var match = keys.filter(function(y) { return obj[y] === lowest }); document.body.innerHTML = '<pre>' +JSON.stringify(match, null, 4)+ '</pre>'; 

Getting the keys, then creating a array of the values that is passed to Math.min.apply to get the lowest value in the object.

Then it's just a matter of filtering the keys for whatever matches the lowest value in the object.

Here's another way using sort

var obj   = {y:10, au:41, w:41, m:11, u:21, t:1, d:1};
var keys  = Object.keys(obj).sort(function(a,b) { return obj[a] - obj[b]; });
var match = keys.filter(function(x) { return obj[x] === obj[keys[0]]; });

Answer 2

This is a solution with Array#reduce() :

 var object = { y: 10, au: 41, w: 41, m: 11, u: 21, t: 1, d: 1 }, result = function (o) { var keys = Object.keys(o); return keys.reduce(function (r, k) { if (o[k] < o[r[0]]) { return [k]; } if (o[k] === o[r[0]]) { r.push(k); } return r; }, [keys.shift()]); }(object); document.write('<pre>' + JSON.stringify(result, 0, 4) + '</pre>');