JS:将数组简化为嵌套对象

const mapped = [[2016, "October", "Monday", { a: 1 }], [2017, "January", "Friday", { a: 1 }], [2017, "January", "Wednesday", { a: 1 }], [2017, "October", "Monday", { a: 1 }]]; const result = mapped.reduce( (acc, [year, month, day, object]) => { let curr = acc[year] = acc[year] || {}; curr = curr[month] = curr[month] || {}; curr = curr[day] = curr[day] || []; curr.push(object); return acc;}, {});console.log(result); .as-console-wrapper { max-height: 100% !important; top: 0; } 使用数组换行如果您确实需要包装数组，则可以对先前的结果应用额外的递归函数: const mapped = [[2016, "October", "Monday", { a: 1 }], [2017, "January", "Friday", { a: 1 }], [2017, "January", "Wednesday", { a: 1 }], [2017, "October", "Monday", { a: 1 }]]; const result = mapped.reduce( (acc, [year, month, day, object]) => { let curr = acc[year] = acc[year] || {}; curr = curr[month] = curr[month] || {}; curr = curr[day] = curr[day] || []; curr.push(object); return acc;}, {});function wrapInArrays(data) { return Array.isArray(data) ? data : Object.entries(data).map ( ([key, value]) => { return { [key]: wrapInArrays(value) }; });}const wrapped = wrapInArrays(result);console.log(wrapped); .as-console-wrapper { max-height: 100% !important; top: 0; } So I have this arrayvar mapped = [[2016, "October", "Monday", {object}], [2017, "January", "Friday", {object}], [2017, "January", "Wednesday", {object}], [2017, "October", "Monday", {object}]]What I want to accomplish is something like this:[{ "2016": [{ "October": [{ "Monday": [{object}] }] }],}, { "2017": [{ "January": [{ "Friday": [{object}] }, { "Wednesday": [{object}] }] }, { "October": [{ "Monday": [{object}] }] }]}]I've been searching around for so long, and I can't find a solution.. By using reduce, I'm getting something like this:[ 2016: [{ "month": "October" }]],[ 2017: [{ "month": "January" }, { "month": "January" }, { "month": "September" }]]So it seems like I'm into something, but still so far away... This is what I'm doing:mapped.reduce((years, array) => { years[array[0]] = years[array[0]] || []; years[array[0]].push({ month: array[1] }) return years; }, []) 解决方案 Not exactly what you specified, but I feel the following script outputs a format that will be most useful -- it only produces arrays at the deepest level:const mapped = [[2016, "October", "Monday", { a: 1 }], [2017, "January", "Friday", { a: 1 }], [2017, "January", "Wednesday", { a: 1 }], [2017, "October", "Monday", { a: 1 }]]; const result = mapped.reduce( (acc, [year, month, day, object]) => { let curr = acc[year] = acc[year] || {}; curr = curr[month] = curr[month] || {}; curr = curr[day] = curr[day] || []; curr.push(object); return acc;}, {});console.log(result); .as-console-wrapper { max-height: 100% !important; top: 0; }With array wrappingIf you really need the wrapping arrays, you can apply an extra recursive function to the previous result:const mapped = [[2016, "October", "Monday", { a: 1 }], [2017, "January", "Friday", { a: 1 }], [2017, "January", "Wednesday", { a: 1 }], [2017, "October", "Monday", { a: 1 }]]; const result = mapped.reduce( (acc, [year, month, day, object]) => { let curr = acc[year] = acc[year] || {}; curr = curr[month] = curr[month] || {}; curr = curr[day] = curr[day] || []; curr.push(object); return acc;}, {});function wrapInArrays(data) { return Array.isArray(data) ? data : Object.entries(data).map ( ([key, value]) => { return { [key]: wrapInArrays(value) }; });}const wrapped = wrapInArrays(result);console.log(wrapped);.as-console-wrapper { max-height: 100% !important; top: 0; } 这篇关于JS:将数组简化为嵌套对象的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！