我如何根据下划线中的值获取键

Question

我有这个对象

{'a': 'test1', 'b': 'test2', 'c': 'test3'}

那我有

[{name: 'test1', selected: true}, {name: 'test3', selected: true}]

现在我想获得在第二个对象中选择为 true 的键的最终列表

['a', 'c']

如何在下划线中做到这一点

我试过了

var inv_obj = _.invert(obj);

                            return _

                                .filter(objectList, function (obj) {
                                    return obj.selected
                                })
                                .map(function (obj, inv_obj) {
                                    return inv_obj[obj] ?:''
                                })

Answer 1

var obj = {'a': 'test1', 'b': 'test2', 'c': 'test3'};
var col = [{name: 'test1', selected: true}, {name: 'test2', selected: false}, {name: 'test3', selected: true}];

var inv_obj = _.invert(obj);

var final = _.filter(col, function(obj) {
    return obj.selected;
}).map(function (obj) {
    return inv_obj[obj.name];
});

console.log(final);

Answer 2

尝试：

var a={'a': 'test1', 'b': 'test2', 'c': 'test3'};
var b=[{name: 'test1', selected: true}, {name: 'test3', selected: true}];

var c=_.pluck(_.where(b, {selected: true}), 'name');
// ['test1', 'test3']

var d=_.invert(a);
console.log(_.values(_.pick(d, c)));

我如何根据下划线中的值获取键

How can i get keys based on values in underscore

javascript

underscore.js