js / reactjs - 如何从两个源构造一个数组？

时间：2017-08-11 10:36:39

标签： javascript arrays

我有两个需要合并的数组：

阵列1：

[ { 'Issues in Version': 'PPW-1075', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1076', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1077', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1078', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1079', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1080', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1081', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1123', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1133', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1134', 'Issues In Progress': '' } ]

阵列2：

 [{ 'Issues In Version': '', 'Issues In Progress': 'PPW-1123' },
  { 'Issues In Version': '', 'Issues In Progress': 'PPW-1133' },
  { 'Issues In Version': '', 'Issues In Progress': 'PPW-1134' } ]

如何合并这些数组以提供以下内容：

[ { 'Issues in Version': 'PPW-1075', 'Issues In Progress': 'PPW-1123' },
  { 'Issues in Version': 'PPW-1076', 'Issues In Progress': 'PPW-1133' },
  { 'Issues in Version': 'PPW-1077', 'Issues In Progress': 'PPW-1134' },
  { 'Issues in Version': 'PPW-1078', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1079', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1080', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1081', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1123', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1133', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1134', 'Issues In Progress': '' } ]

3 个答案:

答案 0 :(得分：1)

Yocu可以生成一个新数组，检查属性是否具有匹配属性的真值。

var array1 =[ { 'Issues In Version': 'PPW-1075', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1076', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1077', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1078', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1079', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1080', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1081', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1123', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1133', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1134', 'Issues In Progress': '' } ],
    array2 = [{ 'Issues In Version': '', 'Issues In Progress': 'PPW-1123' }, { 'Issues In Version': '', 'Issues In Progress': 'PPW-1133' }, { 'Issues In Version': '', 'Issues In Progress': 'PPW-1134' } ],
    result = array1.map((o, i) => ({
        'Issues In Version': o['Issues In Version'] || ((array2[i] || {})['Issues In Version']) || '',
        'Issues In Progress': o['Issues In Progress'] || ((array2[i] || {})['Issues In Progress']) || ''
    }));
  
console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }

任何长度数组的解决方案。

var array1 =[ { 'Issues In Version': 'PPW-1075', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1076', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1077', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1078', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1079', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1080', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1081', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1123', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1133', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1134', 'Issues In Progress': '' } ],
    array2 = [{ 'Issues In Version': '', 'Issues In Progress': 'PPW-1123' }, { 'Issues In Version': '', 'Issues In Progress': 'PPW-1133' }, { 'Issues In Version': '', 'Issues In Progress': 'PPW-1134' } ],
    result = [array1, array2].reduce((r, a) => (a.forEach((o, i) => {
        r[i] = r[i] || {};
        Object.keys(o).forEach(k => r[i][k] = r[i][k] || o[k] || '');
    }), r), []);

  
console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }

答案 1 :(得分：0)

如果您想保留相同的数组，只想添加新属性

var array1 = [{ 'Issues In Version': 'PPW-1075', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1076', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1077', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1078', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1079', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1080', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1081', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1123', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1133', 'Issues In Progress': '' }, { 'Issues In Version': 'PPW-1134', 'Issues In Progress': '' } ]
var array2 = [{ 'Issues in Version': '', 'Issues In Progress': 'PPW-1123' }, { 'Issues In Version': '', 'Issues In Progress': 'PPW-1133' }, { 'Issues In Version': '', 'Issues In Progress': 'PPW-1134' } ]

for (let i = 0, l = array2.length; i < l; i++) {
  array1[i]['Issues In Progress'] = array2[i]['Issues In Progress']
}

console.log(array1)

答案 2 :(得分：0)

这个怎么样？

const first = [
  { 'Issues in Version': 'PPW-1075', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1076', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1077', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1078', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1079', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1080', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1081', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1123', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1133', 'Issues In Progress': '' },
  { 'Issues in Version': 'PPW-1134', 'Issues In Progress': '' }
];

const second = [
  { 'Issues In Version': '', 'Issues In Progress': 'PPW-1123' },
  { 'Issues In Version': '', 'Issues In Progress': 'PPW-1133' },
  { 'Issues In Version': '', 'Issues In Progress': 'PPW-1134' }
];

const merged = new Array(Math.max(first.length, second.length))
  .fill(null)
  .map((item, index) => ({
    'Issues in Version': index < first.length ? first[index]['Issues in Version'] : '',
    'Issues in Progress': index < second.length ? second[index]['Issues In Progress'] : ''
  }));

英文解释

  1. 您创建一个长度 n 的数组，其中 n 是2个数组长度的最大值。如果不能保证第一个数组的长度等于或大于第二个数组，则必须这样做。

  2. 使用占位符值（在本例中为null）填充数组，以便能够迭代它。

  3. 您使用每个迭代的map i 将占位符数组index添加到所需对象的数组中，以获取Issues in Version的值 i 第一个数组中的第一个项目以及第二个数组的 i 项中的Issues In Progress值。三元运算符确保在index超过数组长度的情况下，使用空字符串。

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