如何在 JavaScript 中分离每个 JSON 对象并将它们分组到一个数组中？

3回答

潇潇雨雨

我会使用减少const data = [ { fieldname: 'files0', originalname: 'Screenshot from 2020-05-23 01-52-30.png', },{ fieldname: 'files0', originalname: 'Screenshot from 2020-05-22 08-44-05.png', },{ fieldname: 'files1', originalname: 'Screenshot from 2020-05-30 11-36-42.png', },{ fieldname: 'files1', originalname: 'Screenshot from 2020-05-30 11-36-36.png', },{ fieldname: 'files1', originalname: 'Screenshot from 2020-05-30 11-36-31.png', }],arr = data.reduce((acc, cur) => { const idx = cur.fieldname.replace("files",""); // get 0, 1 if (acc[idx]) acc[idx].push(cur); // if already there, just push else acc[idx] = [cur]; // otherwise initialise return acc;},[]) console.log(arr)注意：组可以在 0 到 9 之间，具体取决于用户输入。我假设没有漏洞，因为这可能会导致稀疏数组，所以data = [ { fieldname : 'files0' }, { fieldname : 'files0' }, { fieldname : 'files3' }, { fieldname : 'files3' }, }会创建一个数组[ [ { fieldname : 'files0' }, { fieldname : 'files0' } ], null, null, [ { fieldname : 'files3' }, { fieldname : 'files3' } ],]

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肥皂起泡泡

我尽量不修改你的逻辑来做到这一点。如果没有files2，filesArray[2] 将为undefined。// Omit other fieldsconst req = {    files: [        { fieldname: "files0", originalname: 'Screenshot from 2020-05-23 01-52-30.png'},        { fieldname: "files0", originalname: 'Screenshot from 2020-05-22 08-44-05.png'},        { fieldname: "files1", originalname: 'Screenshot from 2020-05-30 11-36-42.png'},        { fieldname: "files1", originalname: 'Screenshot from 2020-05-30 11-36-36.png'},        { fieldname: "files1", originalname: 'Screenshot from 2020-05-30 11-36-31.png'},        { fieldname: "files3", originalname: 'Screenshot from 2020-05-30 11-36-42.png'},        { fieldname: "files3", originalname: 'Screenshot from 2020-05-30 11-36-36.png'},        { fieldname: "files3", originalname: 'Screenshot from 2020-05-30 11-36-31.png'}    ]}let filesArray = []for (let file of req.files) {    const thisFileGroup = parseInt(file.fieldname.match(/\d/g).join(''), 10);    if (!filesArray[thisFileGroup]) {        filesArray[thisFileGroup] = []    }    filesArray[thisFileGroup].push(file)}console.log(filesArray[2]) // will be undefinedconsole.log(filesArray[1]) // will be files1 arrayconsole.log(filesArray)

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DIEA

如果您不一定需要按索引排序files[index]在这种情况下，你可以将Array.prototype.reduce()转换为Object。您的对象将按属性（但不是按字母顺序）分组，其中包含一个数组，其中的项目具有相同的属性键。使用Object.values() （如果需要，还可以使用Array.prototype.forEach()）迭代您的对象。fieldnameconst data = [ { fieldname: "files0", originalname: '0-a'}, { fieldname: "files0", originalname: '0-b'}, { fieldname: "files1", originalname: '1-a'}, { fieldname: "files1", originalname: '1-b'}, { fieldname: "files1", originalname: '1-c'},];const byFieldName = data.reduce((ob, d) => { if (!ob.hasOwnProperty(d.fieldname)) ob[d.fieldname] = []; ob[d.fieldname].push(d); return ob;}, {});// console.log(byFieldName); // Uncomment to see how it looks likeconsole.log( Object.values(byFieldName) );

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