根据相同元素合并，一维数组转二维数组some方法

var arr = [{ "occurTm": "2020-10-20", "loc": "中国北京市无名区", "lm": "花无名(地区)乡四环", "rd": "四环", "type": 28, "typeName": "事故易发路段", "roadCode": 7020211, "roadTypeName": "快速路" }, { "occurTm": "2020-10-20", "loc": "中国北京市无名区", "lm": "南无名公益东桥", "rd": "四环公无名", "type": 28, "typeName": "事故易发路段", "roadCode": 7020211, "roadTypeName": "快速路" }, { "occurTm": "2020-10-21", "loc": "中国北京市无名区", "lm": "卢无名乡银河大厦", "rd": "三环", "type": 28, "typeName": "事故易发路段", "roadCode": 7020211, "roadTypeName": "快速路" }, { "occurTm": "2020-10-21", "loc": "中国北京市无名区", "lm": "无名街道", "rd": "万无名路", "type": 28, "typeName": "事故易发路段", "roadCode": 7020211, "roadTypeName": "快速路" }] function getNewArr(arr) { let newArr = [] arr.forEach((locationList, i) => { let index = -1 let alreadyExists = newArr.some((newAddress, j) => { if (locationList.occurTm === newAddress.occurTm) { index = j return true } }) if (!alreadyExists) { newArr.push({ occurTm: locationList.occurTm, loctionArr: [locationList] }) } else { newArr[index].loctionArr.push(locationList) } }) return newArr } console.log(getNewArr(arr))