如何从Nodejs中的JSON对象数组中删除重复项

Question

我试图根据以下JSON的id删除重复条目，但似乎无法正确解析json，我的JSON数组如下所示：

[ '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"57"},{"name":"sample","id":"acc"}]}\n',
  '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"50"},{"name":"sample","id":"ac"}]}\n',
  '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"50"},{"name":"sample","id":"ac"}]}\n',
  '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"50"}]}\n',
]

输出应该是

{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"57"},{"name":"sample","id":"acc"}]}

我的守则如下：

removeDups: async function(listent){
      for (i = 0; i < listent.length; i++){
        console.log(listent.length)
         for (j = 0; j < listent.length; j++){
           console.log(listent[j])
       }
        var standardsList = this.arrUnique(listent);
        console.log("standard", standardsList)
    }
    },

    arrUnique: function (arr) {
      var cleaned = [];
      arr.forEach(function(itm) {
          var unique = true;
          cleaned.forEach(function(itm2) {
              if (_.isEqual(itm, itm2)) unique = false;
          });
          if (unique)  cleaned.push(itm);
      });
      return cleaned;

      }

Answer 1

希望这对你有用：https://jsfiddle.net/c0pkw5ju/

核心职能是：

var val = array.reduce(function (acc, val) {
    return acc.concat(val.entries)
}, [])

console.log(_.unique(val, function (v) {
    return v.id
}))

基本上，您需要将您的\n分离的JSON响应转换为JS对象，该对象可以按指示使用。如果这不起作用的话请告诉我。

输出：

[
  {
    "name": "sample",
    "id": "8d"
  },
  {
    "name": "sample",
    "id": "57"
  },
  {
    "name": "sample",
    "id": "acc"
  },
  {
    "name": "sample",
    "id": "50"
  },
  {
    "name": "sample",
    "id": "ac"
  }
]

最新情况:假设答复如下：

var response = ['{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"57"},{"name":"sample","id":"acc"}]}\n',
    '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"50"},{"name":"sample","id":"ac"}]}\n',
    '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"50"},{"name":"sample","id":"ac"}]}\n',
    '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"50"}]}\n',
]

如果您处理了如下所示的响应：

var array = response.map(function(val) {
    return JSON.parse(val.trim())
})

那么核心功能就会起作用。

Answer 2

运行代码片段，您将看到与您在问题中提到的完全相同的输出。我希望这对你(和其他人)有帮助。:)

​

const data = ['{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"57"},{"name":"sample","id":"acc"}]}\n',
    '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"50"},{"name":"sample","id":"ac"}]}\n',
    '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"50"},{"name":"sample","id":"ac"}]}\n',
    '{"entries":[{"name":"sample","id":"8d"},{"name":"sample","id":"50"}]}\n',
];

// Let us first format it correctly 
const formatted = data.map(x => {
    return JSON.parse(x.trim())
});

// Let's loop over our newly created array and push unique values into a new one

let uniqueNames = [];
let uniqueObj = [];

for(let i = 0; i < formatted.length; i++){    
    if(uniqueNames.indexOf(data[i]._id) === -1){
       uniqueObj.push(data[i])
       uniqueNames.push(data[i]._id);
       }        
    }

// Let's take that one step further and display it exactly as you wanted it to be :)
const iterator = uniqueObj.values();

for (const value of iterator) {
   console.log(value);
}

​