javascript - 过滤对象javascript中的数组

Question

也许是星期五早上，我有一点时间，但不明白为什么这不起作用。

我有这个 JSON

var recipes = [{
            name: "Beef Lasagne",
            ingredients: [
                "mince",
                "pasta",
                "sauce",
                "tomatoes"
            ]}]

我可以这样做:recipes.filter(recipe => recipe.name.includes('e')) 并正确过滤

然而，当我尝试这样做时:recipes.filter(recipe => recipe.ingredients.includes('e'))

我知道我正在尝试在 ex1 中过滤一个字符串，然后在 ex2 中过滤一个数组，我还需要做什么才能使第二个过滤器正常工作？

Answer 1

Array.includes() 将查找特定元素。由于 ingredients 也是一个数组，因此您也需要遍历 ingredients 数组。

正如所写，只有当成分等于:

    ingredients: [
        "mince",
        "pasta",
        "sauce",
        "tomatoes",
        "e"
    ]

所以你可能想要这样的东西:

recipes.filter( recipe => recipe.ingredients.some( ingredient => ingredient.includes( 'e' ) ) );

var recipes = [{
    name: "Beef Lasagne",
    ingredients: [
      "mince",
      "pasta",
      "sauce",
      "tomatoes"
    ]
  },
  {
    name: "Beef Lasagne without e",
    ingredients: [
      "minc",
      "past",
      "tomatos"
    ]
  },
  {
    name: "Beef Lasagne with sauce and no mince",
    ingredients: [
      "sauce",
      "pasta",
      "tomatoes"
    ]
  }
]

console.log(
    recipes.filter( recipe => recipe.ingredients.some( ingredient => ingredient.includes( 'e' ) ) )
)
console.log(
    recipes.filter( recipe => recipe.ingredients.some( ingredient => ingredient.startsWith( 'min' ) ) )
)