javascript - 根据用户输入字符串和菜单下拉项过滤数组

Question

我正在努力过滤我的一个 react 项目中的数组。

我的 React 应用程序有一个搜索栏，它以字符串形式返回 searchQuery 和运动模式菜单，单击时会添加到模式数组中。用户应该能够:

1. 输入搜索查询并过滤数组
2. 使用菜单选择多个模式选项来过滤数组
3. 通过搜索和菜单选择来过滤练习数组。

const searchQuery = "ben";
const pattern = [];

const exercises = [
  {
    name: "bench press",
    movement: ["push", "pull", "squat", "hinge"]
  },
  {
    name: "squat",
    movement: ["push", "pull", "squat", "hinge"]
  },
  {
    name: "squat",
    movement: ["squat", "hinge"]
  },
  {
    name: "pushup",
    movement: ["push", "pull", "squat", "hinge"]
  },
  {
    name: "pullup",
    movement: ["pull", "squat", "hinge"]
  },
  {
    name: "bent over row",
    movement: ["push", "pull", "hinge"]
  }
];

let filteredExercises = [];

if (searchQuery && pattern) {
  filteredExercises = exercises.filter(
    exercise =>
      exercise.name.toLowerCase().indexOf(searchQuery) !== -1 &&
      exercise.movement.some(movement =>
        pattern.some(pattern => pattern == movement)
      )
  );
} else if (pattern.length > 0) {
  filteredExercises = exercises.filter(exercise =>
    exercise.movement.some(movement =>
      pattern.some(pattern => pattern == movement)
    )
  );
} else if (searchQuery) {
  filteredExercises = exercises.filter(
    exercise => exercise.name.toLowerCase().indexOf(searchQuery) !== -1
  );
  console.log(filteredExercises);
}

console.log(filteredExercises);

前两个条件语句起作用并返回正确的数据。一旦我添加第三个条件语句以通过 searchQuery 进行过滤，我就会得到一个空数组作为返回。

谁能帮忙解决这个问题吗？

Answer 1

空数组是truthy，这意味着当pattern为空时，您的第一个if将被触发 - 它永远不会到达您的最后一个否则如果。您可以测试 pattern.length ，它应该可以工作

const searchQuery = "ben";
const pattern = [];

const exercises = [
  {
    name: "bench press",
    movement: ["push", "pull", "squat", "hinge"]
  },
  {
    name: "squat",
    movement: ["push", "pull", "squat", "hinge"]
  },
  {
    name: "squat",
    movement: ["squat", "hinge"]
  },
  {
    name: "pushup",
    movement: ["push", "pull", "squat", "hinge"]
  },
  {
    name: "pullup",
    movement: ["pull", "squat", "hinge"]
  },
  {
    name: "bent over row",
    movement: ["push", "pull", "hinge"]
  }
];

let filteredExercises = [];

if (searchQuery && pattern.length) {
  filteredExercises = exercises.filter(
    exercise =>
      exercise.name.toLowerCase().indexOf(searchQuery) !== -1 &&
      exercise.movement.some(movement =>
        pattern.some(pattern => pattern == movement)
      )
  );
} else if (pattern.length > 0) {
  filteredExercises = exercises.filter(exercise =>
    exercise.movement.some(movement =>
      pattern.some(pattern => pattern == movement)
    )
  );
} else if (searchQuery) {
  filteredExercises = exercises.filter(
    exercise => exercise.name.toLowerCase().indexOf(searchQuery) !== -1
  );
  console.log(filteredExercises);
}

console.log(filteredExercises);