Javascript 多过滤器数组

Question

我的问题是对这个问题的延伸javascript filter array multiple conditions
从那个问题如果过滤器对象是

{address: 'England', name: 'Mark'};

数组是

var users = [{
    name: 'John',
    email: 'johnson@mail.com',
    age: 25,
    address: 'USA'
  },
  {
    name: 'Tom',
    email: 'tom@mail.com',
    age: 35,
    address: 'England'
  },
  {
    name: 'Mark',
    email: 'mark@mail.com',
    age: 28,
    address: 'England'
  }
];

所以答案是

[
  {
    "name": "Mark",
    "email": "mark@mail.com",
    "age": 28,
    "address": "England"
  }
]

这绝对没问题，但我的问题是必须为过滤器对象属性值过滤数组
例如，我的过滤器对象将是 {address: 'England', name: ''} 现在这必须过滤 all names and address England 的数组

Answer 1

您将在用户和每个过滤器对象的条目上使用过滤器

const filter = {address: 'England', name: 'Mark'};

const res = users.filter(user => 
  Object.entries(filter)
  .every(([k,v]) => v === '' || user[k] === v)
);
console.log(res);

<script>
var users = [{
  name: 'John',
  email: 'johnson@mail.com',
  age: 25,
  address: 'USA'
},
  {
    name: 'Tom',
    email: 'tom@mail.com',
    age: 35,
    address: 'England'
  },
  {
    name: 'Mark',
    email: 'mark@mail.com',
    age: 28,
    address: 'England'
  }
];
</script>

Answer 2

从您提到的帖子中的示例中，如果过滤器为空，则继续

var filter = {address: 'England', name: ''}
var users = [{
    name: 'John',
    email: 'johnson@mail.com',
    age: 25,
    address: 'USA'
  },
  {
    name: 'Tom',
    email: 'tom@mail.com',
    age: 35,
    address: 'England'
  },
  {
    name: 'Mark',
    email: 'mark@mail.com',
    age: 28,
    address: 'England'
  }
];

users = users.filter(function(item) {
  for (var key in filter) {
    if (filter[key] == "") continue; // added this:
    if (item[key] === undefined || item[key] != filter[key])
      return false;
  }
  return true;
});
console.log(users)

Answer 3

您可以使用filter 和every 与一些三元逻辑的组合来确定过滤器值是否为空以获得全部。

var users = [{
    name: 'John',
    email: 'johnson@mail.com',
    age: 25,
    address: 'USA'
  },
  {
    name: 'Tom',
    email: 'tom@mail.com',
    age: 35,
    address: 'England'
  },
  {
    name: 'Mark',
    email: 'mark@mail.com',
    age: 28,
    address: 'England'
  }
];

var filter1 = {address: 'England', name: 'Mark'};
var filter2 = {address: 'England', name: ''};

function findResults(input, filterObj){
   return input.filter(
      item => Object.keys(filterObj)
                    .every(r => filterObj[r].length 
                                   ? item[r] == filterObj[r] 
                                   : true)
   )
}

console.log('with address and name', findResults(users,filter1));
console.log('with address only', findResults(users,filter2));

Answer 4

如果我正确理解您的问题，您需要以下输出。 如果这是您正在寻找的 Array.filter 应该足以满足您的用例。 看看code sandbox，我在其中创建了一个函数 filterByObj，它以 arr、filterObj 作为参数并返回给定的输出 { address: "England", name: "" }

Answer 5

您需要 filter 处理这种情况。

var filter1 = {
  address: 'England',
  name: 'Mark'
};

var filter2 = {
  address: 'England',
  name: ''
};

var users = [
  {
    name: 'John',
    email: 'johnson@mail.com',
    age: 25,
    address: 'USA'
  },
  {
    name: 'Tom',
    email: 'tom@mail.com',
    age: 35,
    address: 'England'
  },
  {
    name: 'Mark',
    email: 'mark@mail.com',
    age: 28,
    address: 'England'
  }
];

function filterUser(arr, obj) {
  return arr.filter(function(item) {
    return (
      (obj.address === '' || item.address === obj.address) &&
      (obj.name === '' || item.name === obj.name)
    );
  });
}

console.log(filterUser(users, filter1));
console.log(filterUser(users, filter2));