我想返回从过滤器中获得的值的数组

Question

https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures/intermediate-algorithm-scripting/wherefore-art-thou

我想返回从过滤器中找到值的数组。我从过滤器中得到了一个值，但我想与对象进行比较：

// collection
[
    { first: "Romeo", last: "Montague" },
    { first: "Mercutio", last: null },
    { first: "Tybalt", last: "Capulet" },
]

// source
{ last: "Capulet" }

我最后从过滤器得到：“Capulet”。我需要在我得到它的地方找到整个密钥。

function whatIsInAName(collection, source) {
    var arr = [];
    // Only change code below this line
    let newArr = source.filter((element) => collection.includes(...collection));

    for (let i = 0; i < source.length; i++) {
        if (newArr == source[i]) {
            return source[i];
        }
        //console.log(collection[0])
    }

    console.log(newArr);
}

Answer 1

您可以使用Array.prototype.filter 和Object.entries 和Array.prototype.every 执行此操作，以得出以下简洁的解决方案。

function whatIsInAName(collection, source) {
    return collection.filter(el => {
        return Object.entries(source).every(([key, value]) => {
            return el[key] == value
        })
    })
}

Answer 2

 function whatIsInAName(collection, source) {
  var srcKeys = Object.keys(source);

return collection.filter(function(obj) {
for (var i = 0; i < srcKeys.length; i++) {
  if (
    !obj.hasOwnProperty(srcKeys[i]) ||
    obj[srcKeys[i]] !== source[srcKeys[i]]
  ) {
    return false;
  }
}
return true;
});
}