javascript - 如何过滤一组必须满足javascript中所有条件的记录

Question

我有一组对象，这些对象具有一些基于所选对象的可过滤信息。

我有以下内容，想迭代 selected 中的键并且仅返回满足所有条件的项目(在本例中用户 Amber 的 tagId 为 12 并且 placementId 为 27)。

需要注意的是，如果 selected filter 等于 null，则应将其排除在过滤之外，因为这意味着用户未按此进行过滤。

这将增长到大约 8 个过滤器，因此不想做一些大的 if 语句。我怎么能这样做呢？

var selected = {};
selected["tagId"] = 12;
selected["placementId"] = 27;
selected["locationId"] = null;

var users = [];
users.push({"name":"Joe", "tagIds":[3,4,12], "placementIds": [2,19]});
users.push({"name":"Suzy", "tagIds":[3,4], "placementIds": [2,19, 27]});
users.push({"name":"Amber", "tagIds":[1,12], "placementIds": [2,19, 27]});

function filterBySelected(items){
    var hits = [];
    console.log('within filter by Selected');
    console.log(items);
    for (var key in selected){
        if(selected[key]){ // 
            console.log('you are filtering by: ' + key);
        }
    }
    return hits;
}
var items = filterBySelected(users);
// items should return user object of "Amber"

Answer 1

您可以使用Array#filter和Object.entries(或其polyfill)，如下所示:

var selected = {tagId: 12,placementId: 27};

var users = [
    {"name":"Joe", "tagIds":[3,4,12], "placementIds": [2,19]},
    {"name":"Suzy", "tagIds":[3,4], "placementIds": [2,19, 27]},
    {"name":"Amber", "tagIds":[1,12], "placementIds": [2,19, 27]}
];

function filterBySelected(items){
    return items.filter(item => 
        Object.entries(selected).every(([k, v]) => 
            v == null || (item[k+"s"] || []).includes(v)
        )
    );
}

var items = filterBySelected(users);

console.log(items);

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