我有類似于以下物件陣列：
let violation = [
{
"timestamp": 1637658787661,
"driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7",
"company": "9d8616dd-4689-4689-8812-a2345ccdcfc5",
"message": "CreateHarshAccelerationEvent",
"value": 71,
},
{
"timestamp": 1637658789678,
"driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7",
"company": "9d8616dd-4689-4689-8812-a2345ccdcfc5",
"message": "CreateHarshDecelerationEvent",
"value": 50,
},
{
"timestamp": 1637659776571,
"driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7",
"company": "9d8616dd-4689-4689-8812-a2345ccdcfc5",
"message": "CreateIdlingEvent",
"value": 0,
},
{
"timestamp": 1637660707375,
"driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7",
"company": "9d8616dd-4689-4689-8812-a2345ccdcfc5",
"message": "CreateSpeedingEvent",
"value": 67,
},
{
"timestamp": 1637661519707,
"driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7",
"company": "9d8616dd-4689-4689-8812-a2345ccdcfc5",
"message": "CreateHarshAccelerationEvent",
"value": 71,
},
{
"timestamp": 1637661521773,
"driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7",
"company": "9d8616dd-4689-4689-8812-a2345ccdcfc5",
"message": "CreateHarshDecelerationEvent",
"value": 50,
},
{
"timestamp": 1637661548282,
"driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7",
"company": "9d8616dd-4689-4689-8812-a2345ccdcfc5",
"message": "CreateSpeedingEvent",
"value": 62,
},
{
"timestamp": 1637663230199,
"driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7",
"company": "9d8616dd-4689-4689-8812-a2345ccdcfc5",
"message": "CreateSpeedingEvent",
"value": 66,
},
.....
.....
]
因此，在這里，每個物件都將具有message四個值之一的屬性或鍵，即CreateHarshAccelerationEvent, CreateHarshDecelerationEvent, CreateSpeedingEvent, CreateIdlingEvent。
在這里我需要得到每個鍵的總數。即總計CreateHarshAccelerationEvent和總計CreateHarshDecelerationEvent以及總計CreateIdlingEvent和總計CreateSpeedingEvent
但是條件我必須選擇帶有識別符號的物件總計，該識別符號是驅動程式和公司ID的組合，即
key = company "/" driver
我正在為此執行以下代碼
var violations = []
for (let violation of data){
var key
if ( (violation.company) && (violation.driver) ) {
key = violation.company "/" violation.driver;
let violationType = violation.message;
violations[key].company = violation.company;
violations[key].driver = violation.driver;
}
}
console.log(violations);
我需要結果
[{
"driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7",
"company": "9d8616dd-4689-4689-8812-a2345ccdcfc5",
"CreateHarshAccelerationEvent": "total number of values CreateHarshAccelerationEvent from Array of objects basis on the basis of that custom key i.e. company/driver value",
"CreateHarshDecelerationEvent": "total number of values CreateHarshDecelerationEvent from Array of objects basis on the basis of that custom key i.e. company/driver value",
"CreateIdlingEvent": "total number of values CreateIdlingEvent from Array of objects basis on the basis of that custom key i.e. company/driver value",
"CreateSpeedingEvent": "total number of values CreateSpeedingEvent from Array of objects basis on the basis of that custom key i.e. company/driver value",
}]
uj5u.com熱心網友回復：
Array.reduce 會幫助你。
let violation = [ { "timestamp": 1637658787661, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateHarshAccelerationEvent", "value": 71, }, { "timestamp": 1637658789678, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateHarshDecelerationEvent", "value": 50, }, { "timestamp": 1637659776571, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateIdlingEvent", "value": 0, }, { "timestamp": 1637660707375, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateSpeedingEvent", "value": 67, }, { "timestamp": 1637661519707, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateHarshAccelerationEvent", "value": 71, }, { "timestamp": 1637661521773, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5","message": "CreateHarshDecelerationEvent", "value": 50, }, { "timestamp": 1637661548282, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateSpeedingEvent", "value": 62, }, { "timestamp":1637663230199, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateSpeedingEvent", "value": 66, }];
const result = violation.reduce((acc, curr) => {
const node = acc.find(item => item.driver === curr.driver && item.company === curr.company);
if (node) node[curr.message] ? node[curr.message] = curr.value : node[curr.message] = curr.value
else
acc.push({
driver: curr.driver,
company: curr.company,
[curr.message]: curr.value
});
return acc;
}, []);
console.log(result);uj5u.com熱心網友回復：
你的方法有問題。您不能使用字串作為陣列中的鍵，因此您需要將其更改為 Object
const violations = {}
同樣在您
violations[key].speeding 確保初始化為 0 之前，因為您正在嘗試在undefined此處增加值
uj5u.com熱心網友回復：
您可以使用array#reduce總結相同driver和的不同事件company。
let violation = [ { "timestamp": 1637658787661, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateHarshAccelerationEvent", "value": 71, }, { "timestamp": 1637658789678, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateHarshDecelerationEvent", "value": 50, }, { "timestamp": 1637659776571, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateIdlingEvent", "value": 0, }, { "timestamp": 1637660707375, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateSpeedingEvent", "value": 67, }, { "timestamp": 1637661519707, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateHarshAccelerationEvent", "value": 71, }, { "timestamp": 1637661521773, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5","message": "CreateHarshDecelerationEvent", "value": 50, }, { "timestamp": 1637661548282, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateSpeedingEvent", "value": 62, }, { "timestamp":1637663230199, "driver": "7f5fda5d-86a8-471e-ae32-fcc39deb8fc7", "company": "9d8616dd-4689-4689-8812-a2345ccdcfc5", "message": "CreateSpeedingEvent", "value": 66, }],
result = Object.values(violation.reduce((r, o) => {
const key = o.driver '_' o.company;
r[key] ??= {driver: o.driver, company: o.company};
r[key][o.message] = (r[key][o.message] ?? 0) o.value;
return r;
},{}));
console.log(result);轉載請註明出處，本文鏈接：https://www.uj5u.com/caozuo/364805.html
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