原对象数组

var list = [
		{ melonbody: 8.4, strName: '损伤程度', level: '一等品' },
		{ colorvalue: 8.42, strName: '颜色', level: '一等品' },
		{ diameter: 8.4, strName: '直径', level: '一等品' },
		{ melonbody: 6.41, strName: '损伤程度', level: '二等品' },
		{ colorvalue: 6.4, strName: '颜色', level: '二等品' },
		{ diameter: 6.42, strName: '直径', level: '二等品' },
		{ melonbody: 4.41, strName: '损伤程度', level: '三等品' },
		{ colorvalue: 4.41, strName: '颜色', level: '三等品' },
		{ diameter: 4.42, strName: '直径', level: '三等品' }
];

目标对象数组

demo = [
{ melonbody: 8.4, level: '一等品', colorvalue: 8.42, diameter: 8.4 },
{ melonbody: 6.41, level: '二等品', colorvalue: 6.4, diameter: 6.42 },
{ melonbody: 4.41, level: '三等品', colorvalue: 4.41, diameter: 4.42 }
];

实现方法：

var list = [
		{ melonbody: 8.4, strName: '损伤程度', level: '一等品' },
		{ colorvalue: 8.42, strName: '颜色', level: '一等品' },
		{ diameter: 8.4, strName: '直径', level: '一等品' },
		{ melonbody: 6.41, strName: '损伤程度', level: '二等品' },
		{ colorvalue: 6.4, strName: '颜色', level: '二等品' },
		{ diameter: 6.42, strName: '直径', level: '二等品' },
		{ melonbody: 4.41, strName: '损伤程度', level: '三等品' },
		{ colorvalue: 4.41, strName: '颜色', level: '三等品' },
		{ diameter: 4.42, strName: '直径', level: '三等品' }
];

let level = '';
let demo = [];
let num = -1;
for (let key of list) {
	for (let item in key) {
		if (level != key.level) {
			level = key.level;
			num++;
			demo[num] = {};
		}
		item != 'strName' ? (demo[num][item] = key[item]) : '';
	}
}
console.log(demo);