Question

我想获取我的js对象中所有menge键的总和并将其存储在变量中。有人可以帮我解决这个问题吗？我的对象的片段：

var obj = {
  "_15800175": {
    "posID": "159469",
    "scanID": "22597",
    "anr": "15800175",
    "TVanr": "",
    "code": "G-09-27-2E",
    "ean": "4710069680575",
    "marke": "fox",
    "bez": "jersey yellow",
    "bez2": "size xl",
    "menge": "1",
    "ve": "St\u00fcck",
    "Dimensionstext": "TT9857BG\r\n",
    "Langtext": ""
  },
  "_15100027": {
    "posID": "159471",
    "scanID": "22597",
    "anr": "15100027",
    "TVanr": "",
    "code": "G-11-03-2A",
    "ean": "4712511825411",
    "marke": "fox",
    "bez2": "jersey L",
    "menge": "1",
    "ve": "St\u00fcck",
    "Dimensionstext": "blue\r\n",
    "Langtext": ""
  }
}

Answer 1

您可以像下面这样使用Object.values()和Array.reduce()：

var obj = {
  "_15800175": {
    "posID": "159469",
    "scanID": "22597",
    "anr": "15800175",
    "TVanr": "",
    "code": "G-09-27-2E",
    "ean": "4710069680575",
    "marke": "fox",
    "bez": "jersey yellow",
    "bez2": "size xl",
    "menge": "1",
    "ve": "St\u00fcck",
    "Dimensionstext": "TT9857BG\r\n",
    "Langtext": ""
  },
  "_15100027": {
    "posID": "159471",
    "scanID": "22597",
    "anr": "15100027",
    "TVanr": "",
    "code": "G-11-03-2A",
    "ean": "4712511825411",
    "marke": "fox",
    "bez2": "jersey L",
    "menge": "1",
    "ve": "St\u00fcck",
    "Dimensionstext": "blue\r\n",
    "Langtext": ""
  },
  "dummy": {
    "menge": "not-convertable-to-integer"
  },
   "dummy2": {
    // This item does NOT have "menge" property
  }
}

var sumMenge = Object.values(obj).reduce((sum, item) => sum + (!isNaN(+item.menge) || 0),0);
//                                                                    ^^^ This is to convert item.menge to number

console.log(sumMenge);

希望这会有所帮助

Answer 2

您可以做的是迭代主对象的键，然后将其减少为总和，即： Object.keys(obj).reduce((acc, key) => acc = obj[key].menge + acc, 0)

Answer 3

获取键数组后使用string general = doc.SelectSingleNode("/files/file[not(@product)]").InnerText;

.reduce()

Answer 4

您需要将对象键放入数组中。

var id=Object.keys(obj); //get all keys
var menge=0;// init...
for (i=0;i<id.length;i++){// run over all keys found
  menge=menge+obj[id[i]].menge; /add the things
}
console.log(menge);//see result

请参阅Object.keys

Answer 5

您可以使用for (prop in obj)遍历对象的属性名称。然后，您可以简单地使用total += +obj[prop].menge || 0;。在这里+obj[prop].menge将转换为number。 +obj[prop].menge || 0;如果对象不包含0属性，则此行将返回menge。

var obj = {
  "_15800175": {
    "posID": "159469",
    "scanID": "22597",
    "anr": "15800175",
    "TVanr": "",
    "code": "G-09-27-2E",
    "ean": "4710069680575",
    "marke": "fox",
    "bez": "jersey yellow",
    "bez2": "size xl",
    "menge": "1",
    "ve": "St\u00fcck",
    "Dimensionstext": "TT9857BG\r\n",
    "Langtext": ""
  },
  "_15100027": {
    "posID": "159471",
    "scanID": "22597",
    "anr": "15100027",
    "TVanr": "",
    "code": "G-11-03-2A",
    "ean": "4712511825411",
    "marke": "fox",
    "bez2": "jersey L",
    "menge": "1",
    "ve": "St\u00fcck",
    "Dimensionstext": "blue\r\n",
    "Langtext": ""
  }
}

let total = 0;
for (prop in obj) { 
  total += +obj[prop].menge || 0;
}

console.log(total);

获取javascript对象中特定键的总和

5 个答案: