javascript - 数组嵌套循环无法按预期工作

Question

我正在努力完成以下...

给定数组蛋糕:

const cakes = [
    {id: 1, name: 'chocolate'},
    {id: 2, name: 'strawberry'},
    {id: 3, name: 'mint'}
]

数组“最喜欢的蛋糕”为:

const favCakes = [
    {id: 1, cakeId: 1},
    {id: 2, cakeId: 2}
]

我想在控制台上记录 FAVORITE CAKES 和 NOT FAVORITE CAKES，所以我希望得到这样的结果:

FAVORITE CAKES: 'chocolate'
FAVORITE CAKES: 'strawberry'
NOT FAVORITE CAKES: 'mint'

但正如您从下面的代码片段中看到的那样，它并没有像预期的那样工作。我究竟做错了什么？感谢您的帮助。

const cakes = [
    {id: 1, name: 'chocolate'},
    {id: 2, name: 'strawberry'},
    {id: 3, name: 'mint'}
]

// favorite cakes for logged in user
const favCakes = [
    {id: 1, cakeId: 1},
    {id: 2, cakeId: 2}
]

for (const cake of cakes) {
    for (const fav of favCakes) {
        if (cake.id === fav.cakeId) {
            console.log('FAVORITE CAKE: ', cake.name )
        }
        else if (cake.id !== fav.cakeId) {
            console.log('NOT FAVORITE CAKE: ', cake.name )
        }
    }
}

Answer 1

您过早地检查不喜欢的内容。只有浏览完所有收藏夹后才能确定不喜欢:

for (const cake of cakes) {
    let isFavorite = false; // assume

    for (const fav of favCakes) {
        if (cake.id === fav.cakeId) {
            console.log('FAVORITE CAKE: ', cake.name)
            isFavorite = true;
            break;
        }
    }

    if ( ! isFavorite ) {
        console.log( 'NOT FAVORITE CAKE: ', cake.name )
    }

}