对象数组，在键匹配的地方组合值。 带下划线

Question

给定以下数组：

[  
 {  
      "real":104.1530776708426,
      "workHour":8,
      "value":null
   },
   {  
      "real":71.53948769310401,
      "workHour":9
   },
   {  
      "real":97.84076993321577,
      "workHour":10
   },
   {  
      "real":115.72564185649178,
      "workHour":11
   },
   {  
      "real":79.95589800993977,
      "workHour":12
   },
   {  
      "real":91.52846219558896,
      "workHour":13
   },
   {  
      "real":57.86282092824589,
      "workHour":14
   },
   {  
      "real":148.33923183423036,
      "workHour":15
   },
   {  
      "real":125.19410346293202,
      "workHour":16
   },
   {  
      "real":67.33128253468612,
      "workHour":17
   },
   {  
      "real":55.75871834903695,
      "workHour":18
   },
   {  
      "real":102.04897509163365,
      "workHour":19
   },
   {  
      "real":132.55846249016332,
      "workHour":20
   },
   {  
      "real":138.87077022779013,
      "workHour":21
   },
   {  
      "real":60,
      "workHour":8
   },
   {  
      "real":52,
      "workHour":9
   },
   {  
      "real":114,
      "workHour":10
   },
   {  
      "real":115,
      "workHour":11
   },
   {  
      "real":92,
      "workHour":12
   },
   {  
      "real":102,
      "workHour":13
   },
   {  
      "real":54,
      "workHour":14
   },
   {  
      "real":62,
      "workHour":15
   },
   {  
      "real":133,
      "workHour":16
   },
   {  
      "real":116,
      "workHour":17
   },
   {  
      "real":106,
      "workHour":18
   },
   {  
      "real":115,
      "workHour":19
   },
   {  
      "real":115,
      "workHour":20
   },
   {  
      "real":125,
      "workHour":21
   }
]

我如何才能找到其中workHour匹配，并结合real呢？ 我用纯JS做到的

 const array = [{"real":104.1530776708426,"workHour":8,"value":null},{"real":71.53948769310401,"workHour":9},{"real":97.84076993321577,"workHour":10},{"real":115.72564185649178,"workHour":11},{"real":79.95589800993977,"workHour":12},{"real":91.52846219558896,"workHour":13},{"real":57.86282092824589,"workHour":14},{"real":148.33923183423036,"workHour":15},{"real":125.19410346293202,"workHour":16},{"real":67.33128253468612,"workHour":17},{"real":55.75871834903695,"workHour":18},{"real":102.04897509163365,"workHour":19},{"real":132.55846249016332,"workHour":20},{"real":138.87077022779013,"workHour":21},{"real":60,"workHour":8},{"real":52,"workHour":9},{"real":114,"workHour":10},{"real":115,"workHour":11},{"real":92,"workHour":12},{"real":102,"workHour":13},{"real":54,"workHour":14},{"real":62,"workHour":15},{"real":133,"workHour":16},{"real":116,"workHour":17},{"real":106,"workHour":18},{"real":115,"workHour":19},{"real":115,"workHour":20},{"real":125,"workHour":21}]; var map = {}; for (var i=0; i<array.length; i++) { var obj = array[i], id = obj.workHour; if (id in map) { // we know this id already // get the object and sum properties map[id].real += obj.real; } else // create a new one map[id] = { workHour: id, real: obj.real, }; } console.log(map) 

如何使用ES6？ 或下划线？

Answer 1

使用Array#reduce循环数组，以创建具有组合值的新对象：

 var data = [{"real":104.1530776708426,"workHour":8,"value":null},{"real":71.53948769310401,"workHour":9},{"real":97.84076993321577,"workHour":10},{"real":115.72564185649178,"workHour":11},{"real":79.95589800993977,"workHour":12},{"real":91.52846219558896,"workHour":13},{"real":57.86282092824589,"workHour":14},{"real":148.33923183423036,"workHour":15},{"real":125.19410346293202,"workHour":16},{"real":67.33128253468612,"workHour":17},{"real":55.75871834903695,"workHour":18},{"real":102.04897509163365,"workHour":19},{"real":132.55846249016332,"workHour":20},{"real":138.87077022779013,"workHour":21},{"real":60,"workHour":8},{"real":52,"workHour":9},{"real":114,"workHour":10},{"real":115,"workHour":11},{"real":92,"workHour":12},{"real":102,"workHour":13},{"real":54,"workHour":14},{"real":62,"workHour":15},{"real":133,"workHour":16},{"real":116,"workHour":17},{"real":106,"workHour":18},{"real":115,"workHour":19},{"real":115,"workHour":20},{"real":125,"workHour":21}]; var result = data.reduce(function(r, o) { if (r[o.workHour]) { r[o.workHour].real += o.real } else { r[o.workHour] = { workHour: o.workHour, real: o.real } } return r; }, {}); console.log(result); 

Answer 2

使用lodash（/ underscore），它使用_.reduce()和_.clone()来构建聚合对象。 然后使用_.values()将这个对象的值输出为类似于您输入数组的对象数组。

 var data = [{"real":104.1530776708426,"workHour":8,"value":null},{"real":71.53948769310401,"workHour":9},{"real":97.84076993321577,"workHour":10},{"real":115.72564185649178,"workHour":11},{"real":79.95589800993977,"workHour":12},{"real":91.52846219558896,"workHour":13},{"real":57.86282092824589,"workHour":14},{"real":148.33923183423036,"workHour":15},{"real":125.19410346293202,"workHour":16},{"real":67.33128253468612,"workHour":17},{"real":55.75871834903695,"workHour":18},{"real":102.04897509163365,"workHour":19},{"real":132.55846249016332,"workHour":20},{"real":138.87077022779013,"workHour":21},{"real":60,"workHour":8},{"real":52,"workHour":9},{"real":114,"workHour":10},{"real":115,"workHour":11},{"real":92,"workHour":12},{"real":102,"workHour":13},{"real":54,"workHour":14},{"real":62,"workHour":15},{"real":133,"workHour":16},{"real":116,"workHour":17},{"real":106,"workHour":18},{"real":115,"workHour":19},{"real":115,"workHour":20},{"real":125,"workHour":21}]; var result = _.values(_.reduce(data, (sumObj, curr) => { if (sumObj[curr.workHour]) sumObj[curr.workHour].real += curr.real; else sumObj[curr.workHour] = _.clone(curr); return sumObj; }, {})); console.log(result); 

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