javascript - 将对象数组更改为 CSV 模式

Question

我有以下数组:

var objRow = [
    {
        2011-09-20 : [0, 100, 0],
        customerID : C1101,
        ANI : 1234
    },
    {
        2011-09-25 : [0, 0, 0],
        customerID : C1101,
        ANI : 1234
    },
    {
        2011-09-20 : [0, 500, 0],
        customerID : C1102,
        ANI : 5678
    },
    {
        2011-09-22 : [0, 0, 50],
        customerID : C1102,
        ANI : 5678
    }
]

我想从上面的数组创建 CSV 数据。但是，我在将该数组更改为 CSV 模式时遇到问题:

1234, C1101, 0, 0, 100, 0, 0, 0
5678, C1102, 0, 0, 500, 0, 0, 50

我尝试使用reduce对customerID进行分组，因为每个对象中的第一个索引是日期。我有一些日期数组:

var dateArr = ["2011-09-20", "2011-09-22", "2011-09-25"];

这是我的代码:

var result = objRow.reduce(function(prev, curr, index, arr) {
    var num = curr["customerID"];

    if (!prev[num]) {
        prev[num] = [];
    }

    for (var j = 0; j < dateArr.length; j++) {
        prev[num].push(curr[dateArr[j]]);
    }

    return prev;
}, {});

更新问题用于date索引中的数字组合。我使用这个规则:

[0, 100, 0] // from first Object
[0, 0, 0] // from second Object


fistObject_firstIndex, secondObject_firstIndex, firstObject_secondIndex, secondObject_secondIndex, firstObject_thirdIndex, secondObject_thirdIndex
0, 0, 100, 0, 0, 0

上，下，上，下，上，下......

如何创建上面的 CSV 模式？谢谢...

Answer 1

我认为这会给你你想要的结果:

var objRow = [{
  date: 2011-09-20,
  nums: [0, 100, 0],
  customerID: "C1101",
  ANI: 1234
}, {
  date: 2011-09-25,
  nums: [0, 0, 0],
  customerID: "C1101",
  ANI: 1234
}, {
  date: 2011-09-20,
  nums: [0, 500, 0],
  customerID: "C1102",
  ANI: 5678
}, {
  date: 2011-09-22,
  nums: [0, 0, 50],
  customerID: "C1102",
  ANI: 5678
}];


//CREATE CSV-FORMATTED STRINGS
var csvLine = "";
var numsArray = new Array();
for (var i=0; i<objRow.length; i++) {
  //check if this is the first element with a new 'ANI' (which means a new CSV line starts)
  if (objRow[i-1]==(undefined||null) || objRow[i].ANI!=objRow[i-1].ANI) {
    //if so, start a new string
    csvLine = objRow[i].ANI +", "+ objRow[i].customerID +", "; //add the 'ANI' and 'customerID'
    numsArray.length = 0; //clear array
    numsArray.push(objRow[i].nums); //store the 'nums' in a separate array
  } else {
    //if not, add to the existing string
    numsArray.push(objRow[i].nums); //store the 'nums' in a separate array
  }

  //check if this is the last element with the same 'ANI' (which means this CSV line is complete)
  if (objRow[i+1]==(undefined||null) || objRow[i].ANI!=objRow[i+1].ANI) {
    //add the 'nums' of every object in intertwining order (every 1st, every 2nd, etc.)
    for (var k=0; k<numsArray[0].length; k++) {
      for (var j=0; j<numsArray.length; j++) {
        csvLine += numsArray[j][k].toString() +", ";
      }
    }
    //remove the last comma
    if (csvLine.substring(csvLine.length-2) == ", ") {
      csvLine = csvLine.substring(0,csvLine.length-2);
    }
    //output the CSV line
    document.getElementById("csv").innerHTML += csvLine + "<br />";
  }
}

<div id="csv"></div>

( fiddle :http://jsfiddle.net/5gyp3ce6/16/ )

我必须稍微更改一下您的数组，因为要使其工作，数组键必须全部相同。
另外，我必须将 ID 更改为字符串，否则无法定义它们。

而不是将其写入 <div>最后，您当然可以将该行添加到另一个变量中，将其写入文件或其他内容。

如果代码中的注释不够清楚，请留下评论，我会尽力解释得更好。