從具有最小值的javascript對象獲取密鑰

Question

我想從具有極小值的javascript對象獲取密鑰。

var myobj = {"1632":45,"1856":12,"1848":56,"1548":34,"1843":88,"1451":55,"4518":98,"1818":23,"3458":45,"1332":634,"4434":33}; 

我必須得到具有最小值的鑰匙。即：

1856 

努力去獲得。我是新的對象操縱。

Answer 1

你可以試試這個：

var xx={"1632":45,"1856":12,"1848":56,"1548":34,"1843":88,"1451":55,"4518":98,"1818":23,"3458":45,"1332":634,"4434":33}; 
 

 

 
var z=_.keys(_.pick(xx, function(value, key, object) { 
 
return (value==_.min(_.values(xx))); 
 
}))[0]; 
 

 
document.getElementById("my_div").innerHTML=z;

<script src="http://underscorejs.org/underscore-min.js"></script> 
 

 
<div id="my_div"> </div>

第三方庫underscore.js已被使用。你應該嘗試一下：

http://underscorejs.org/underscore-min.js

Answer 2

腠可以使用Array#reduce。

var object = { "1632": 45, "1856": 12, "1848": 56, "1548": 34, "1843": 88, "1451": 55, "4518": 98, "1818": 23, "3458": 45, "1332": 634, "4434": 33 }, 
 
    key = Object.keys(object).reduce(function (r, a, i) { 
 
     return !i || +object[a] < +object[r] ? a : r; 
 
    }, undefined); 
 

 
console.log(key);

Answer 3

遍歷對象的屬性和獲得基於最小值鍵。

var myjson = { 
 
    "1632": 45, 
 
    "1856": 12, 
 
    "1848": 56, 
 
    "1548": 34, 
 
    "1843": 88, 
 
    "1451": 55, 
 
    "4518": 98, 
 
    "1818": 23, 
 
    "3458": 45, 
 
    "1332": 634, 
 
    "4434": 33 
 
}; 
 

 
// get object keys array 
 
var keys = Object.keys(myjson), 
 
    // set initial value as first elemnt in array 
 
    res = keys[0]; 
 

 
// iterate over array elements 
 
keys.forEach(function(v) { 
 
    // compare with current property value and update with the min value property 
 
    res = +myjson[res] > +myjson[v] ? v : res; 
 
}); 
 

 
console.log(res);

Answer 4

學習的方法，通過對循環運行：

var myobj = {"1632":45,"1856":12,"1848":56,"1548":34,"1843":88,"1451":55,"4518":98,"1818":23,"3458":45,"1332":634,"4434":33}; 

// Get the keys of myobj so we can iterate through it 
var keys = Object.keys(myobj); 

// Iterate through all the key values 
var minimumKey = keys[0]; 
for(var i = 1; i < keys.length; i++){ 
    var minimum = myobj[minimumKey]; 
    var value = myobj[keys[i]]; 
    if(minimum > value) minimumKey = keys[i]; 
} 

console.log(minimumKey, myobj[minimumKey]); 

一個功能更強大的方法：

var myobj = {"1632":45,"1856":12,"1848":56,"1548":34,"1843":88,"1451":55,"4518":98,"1818":23,"3458":45,"1332":634,"4434":33}; 

var minimum = Object.keys(myobj).map(function(key){ 
    return { 
     "key": key, 
     "value": myobj[key] 
    } 
}).sort(function(a, b){ 
    return a.value - b.value 
})[0]; 

console.log(minimum); 
console.log(minimum.key); 
console.log(minimum.value);