var arr = [{
"name": "语文",
"fraction": 80
}, {
"name": "数学",
"fraction": 70
}, {
"name": "语文",
"fraction": 50
}, {
"name": "语文",
"fraction": 90
}, {
"name": "数学",
"fraction": 100
}, {
"name": "数学",
"fraction": 55
}, {
"name": "语文",
"fraction": 99
}]
第一种方式
var res =[];
var narr=[];
for(var i =0;i<arr.length;i++){
var n = res.indexOf(arr[i].name);
if(n == -1){
res.push(arr[i].name);
narr.push({"name":arr[i].name,fraction:[arr[i].fraction]})
}else{
narr[n].fraction.push(arr[i].fraction)
}
}
console.log(narr)
第二种方式：
arr = arr.map(function(item, index, arr) {
const i = arr.find(_item => item.name === _item.name);
if(i !== item) {
i.fraction.push(item.fraction);
return undefined;
} else {
i.fraction = [i.fraction];
return i;
}
}).filter(item => item !== undefined);