如果我有一个JavaScript对象,如:
var list = {
"you": 100,
"me": 75,
"foo": 116,
"bar": 15
};
是否有一种方法可以根据值对属性进行排序?最后得到
list = {
"bar": 15,
"me": 75,
"you": 100,
"foo": 116
};
如果我有一个JavaScript对象,如:
var list = {
"you": 100,
"me": 75,
"foo": 116,
"bar": 15
};
是否有一种方法可以根据值对属性进行排序?最后得到
list = {
"bar": 15,
"me": 75,
"you": 100,
"foo": 116
};
当前回答
对象按值排序(DESC)
function sortObject(list) {
var sortable = [];
for (var key in list) {
sortable.push([key, list[key]]);
}
sortable.sort(function(a, b) {
return (a[1] > b[1] ? -1 : (a[1] < b[1] ? 1 : 0));
});
var orderedList = {};
for (var i = 0; i < sortable.length; i++) {
orderedList[sortable[i][0]] = sortable[i][1];
}
return orderedList;
}
其他回答
感谢@orad在TypeScript中提供了答案。现在,我们可以在JavaScript中使用下面的代码片断。
function sort(obj,valSelector) { const sortedEntries = Object.entries(obj) .sort((a, b) => valSelector(a[1]) > valSelector(b[1]) ? 1 : valSelector(a[1]) < valSelector(b[1]) ? -1 : 0); return new Map(sortedEntries); } const Countries = { "AD": { "name": "Andorra", }, "AE": { "name": "United Arab Emirates", }, "IN": { "name": "India", }} // Sort the object inside object. var sortedMap = sort(Countries, val => val.name); // Convert to object. var sortedObj = {}; sortedMap.forEach((v,k) => { sortedObj[k] = v }); console.log(sortedObj); //Output: {"AD": {"name": "Andorra"},"IN": {"name": "India"},"AE": {"name": "United Arab Emirates"}}
对象按值排序(DESC)
function sortObject(list) {
var sortable = [];
for (var key in list) {
sortable.push([key, list[key]]);
}
sortable.sort(function(a, b) {
return (a[1] > b[1] ? -1 : (a[1] < b[1] ? 1 : 0));
});
var orderedList = {};
for (var i = 0; i < sortable.length; i++) {
orderedList[sortable[i][0]] = sortable[i][1];
}
return orderedList;
}
JavaScript对象根据定义是无序的(参见ECMAScript语言) 规范,第8.6节)。语言规范甚至不能保证,如果你连续迭代一个对象的属性两次,第二次它们会以相同的顺序出现。
如果你需要对事物进行排序,可以使用数组和array .prototype.sort方法。
谢谢你,继续回答@Nosredna
现在我们知道对象需要转换为数组,然后对数组排序。这对于按字符串排序数组(或转换对象为数组)非常有用:
Object {6: Object, 7: Object, 8: Object, 9: Object, 10: Object, 11: Object, 12: Object}
6: Object
id: "6"
name: "PhD"
obe_service_type_id: "2"
__proto__: Object
7: Object
id: "7"
name: "BVC (BPTC)"
obe_service_type_id: "2"
__proto__: Object
//Sort options
var sortable = [];
for (var vehicle in options)
sortable.push([vehicle, options[vehicle]]);
sortable.sort(function(a, b) {
return a[1].name < b[1].name ? -1 : 1;
});
//sortable => prints
[Array[2], Array[2], Array[2], Array[2], Array[2], Array[2], Array[2]]
0: Array[2]
0: "11"
1: Object
id: "11"
name: "AS/A2"
obe_service_type_id: "2"
__proto__: Object
length: 2
__proto__: Array[0]
1: Array[2]
0: "7"
1: Object
id: "7"
name: "BVC (BPTC)"
obe_service_type_id: "2"
__proto__: Object
length: 2
a = { b: 1, p: 8, c: 2, g: 1 }
Object.keys(a)
.sort((c,b) => {
return a[b]-a[c]
})
.reduce((acc, cur) => {
let o = {}
o[cur] = a[cur]
acc.push(o)
return acc
} , [])
输出= [{p: 8}, {c: 2}, {b: 1}, {g: 1}]