如何从打字稿中的数组中清除元素值？答案

【问题标题】：How do I clear element values from an array in typescript?如何从打字稿中的数组中清除元素值？
【发布时间】：2018-10-20 09:43:06
【问题描述】：

这里有一个数组。

  let dataList=  [
  {
    "VersionId": 475,
    "DocumentVersionFieldId": 1105,
    "VariantId": 4597,
    "ElementId": 1019,
    "FuelTypeId": 4,
    "VariantStructureWeek": "201817",
    "SalesVersion": "1",
    "MarketingCode": "1",
    "Option": "1",
    "SequenceNo": 1,
    "VariantExtendedValue": [],    
    "cocVariantElementValues": [
      {
        "VersionId": 475,
        "DocumentVersionFieldId": 1105,
        "VariantId": 4597,
        "ElementId": 1017,
        "ElementVariantId": 9548,
        "VariantValue": "uy",
        "IsRecordVisible": false,
        "cocElementLanguageDataCollection": [
          {
            "ElementVariantId": 9548,
            "LanguageId": 0,
            "LanguageCode": "EN",
            "TranslationValue": "uy"
          },
          {
            "ElementVariantId": 9548,
            "LanguageId": 0,
            "LanguageCode": "AL",
            "TranslationValue": "jh"
          },
          {
            "ElementVariantId": 9548,
            "LanguageId": 0,
            "LanguageCode": "DE",
            "TranslationValue": "hj"
          },          
          {
            "ElementVariantId": 9548,
            "LanguageId": 0,
            "LanguageCode": "UR",
            "TranslationValue": "jh"
          }
        ]
      }
    
    ],
    "isRowDeleted": false,
    "operationIndicators": 0,
    "isMultiLanguage": true,
    "IsRecordVisible": true,
    "isShowUp": false,
    "IsNewRow": false
  }
]

我想从上面的数组中清除下面元素的值。

我想从cocVariantElementValues数组中清除VariantValue元素
我想从cocElementLanguageDataCollection数组中清除TranslationValue元素

这是预期的。

    [
      {
        "VersionId": 475,
        "DocumentVersionFieldId": 1105,
        "VariantId": 4597,
        "ElementId": 1019,
        "FuelTypeId": 4,
        "VariantStructureWeek": "201817",
        "SalesVersion": "1",
        "MarketingCode": "1",
        "Option": "1",
        "SequenceNo": 1,
        "VariantExtendedValue": [],    
        "cocVariantElementValues": [
          {
            "VersionId": 475,
            "DocumentVersionFieldId": 1105,
            "VariantId": 4597,
            "ElementId": 1017,
            "ElementVariantId": 9548,
            "VariantValue": "",//here
            "IsRecordVisible": false,
            "cocElementLanguageDataCollection": [
              {
                "ElementVariantId": 9548,
                "LanguageId": 0,
                "LanguageCode": "EN",
                "TranslationValue": "",//here
              },
              {
                "ElementVariantId": 9548,
                "LanguageId": 0,
                "LanguageCode": "AL",
                "TranslationValue": "",//here
              },
              {
                "ElementVariantId": 9548,
                "LanguageId": 0,
                "LanguageCode": "DE",
                "TranslationValue": "",//here
              },          
              {
                "ElementVariantId": 9548,
                "LanguageId": 0,
                "LanguageCode": "UR",
                "TranslationValue": "",//here
              }
            ]
          }
        
        ],
        "isRowDeleted": false,
        "operationIndicators": 0,
        "isMultiLanguage": true,
        "IsRecordVisible": true,
        "isShowUp": false,
        "IsNewRow": false
      }
    ]

有没有直接的方法，还是我需要循环并手动删除它们？

【问题讨论】：

能否告诉我投反对票的原因？
你可以使用数组foreach来做。
@HassanImam 在 ECMascript 6 中没有 foreach 是否可行？
@RameshRajendran 希望你能接受我的回答 :)
@RameshRajendran 我不期待代码，离开它，我认为这是为了互相帮助，甚至接受我的回答你不会失去任何东西，但我很高兴

标签： javascript arrays typescript ecmascript-6

【解决方案1】：

感谢@ppl

我通过在我的场景中使用多个 .map() 得到它。

dataList.map(function(x) { 
      x.cocVariantElementValues.map(function(y) { 
      y['VariantValue'] = ''; 
      y.cocElementLanguageDataCollection.map(function(z) { 
      z['TranslationValue'] = ''; 
      return z
    });
      return y;
    });
      return x;
    });

成功的片段

let dataList=  [
  {
    "VersionId": 475,
    "DocumentVersionFieldId": 1105,
    "VariantId": 4597,
    "ElementId": 1019,
    "FuelTypeId": 4,
    "VariantStructureWeek": "201817",
    "SalesVersion": "1",
    "MarketingCode": "1",
    "Option": "1",
    "SequenceNo": 1,
    "VariantExtendedValue": [],    
    "cocVariantElementValues": [
      {
        "VersionId": 475,
        "DocumentVersionFieldId": 1105,
        "VariantId": 4597,
        "ElementId": 1017,
        "ElementVariantId": 9548,
        "VariantValue": "uy",
        "IsRecordVisible": false,
        "cocElementLanguageDataCollection": [
          {
            "ElementVariantId": 9548,
            "LanguageId": 0,
            "LanguageCode": "EN",
            "TranslationValue": "uy"
          },
          {
            "ElementVariantId": 9548,
            "LanguageId": 0,
            "LanguageCode": "AL",
            "TranslationValue": "jh"
          },
          {
            "ElementVariantId": 9548,
            "LanguageId": 0,
            "LanguageCode": "DE",
            "TranslationValue": "hj"
          },          
          {
            "ElementVariantId": 9548,
            "LanguageId": 0,
            "LanguageCode": "UR",
            "TranslationValue": "jh"
          }
        ]
      }
    
    ],
    "isRowDeleted": false,
    "operationIndicators": 0,
    "isMultiLanguage": true,
    "IsRecordVisible": true,
    "isShowUp": false,
    "IsNewRow": false
  }
]

let result = dataList.map(function(x) { 
  x.cocVariantElementValues.map(function(y) { 
  y['VariantValue'] = ''; 
  y.cocElementLanguageDataCollection.map(function(z) { 
  z['TranslationValue'] = ''; 
  return z
});
  return y;
});
  return x;
});

console.log(result)

【讨论】：

【解决方案2】：

如果不循环遍历所有元素，您将无法做到这一点，但是您可以使用一些快捷方式来代替 for：

array.map(function(x) { 
  x['VariantValue'] = ''; 
  return x
});

或者你也可以使用这个，它是 es6 胖箭头函数

array.map(x=>x['VariantValue']='');

以上代码未经测试，可能存在语法错误。

【讨论】：