如何使用“;”将上传的 CSV 文件转换为 UFT-8分隔符？

Question

我有一个导入程序，应该从第三方程序上传一个特殊文件。该文件的结构如下：

TITLE,DESCRIPTION,PRICE,CURRENCY_CODE,QUANTITY,TAGS
"This is the file title","This is the file description and it can include line breaks

Size: 16x16
Weight: 1,5
for example here

more information.",12.99,USD,10,"Tag1,Tag2,Tag3"
"Next line","This is the file description and it can include line breaks

Size: 16x16
Weight: 1,5
for example here

more information.",12.99,USD,10,"Tag1,Tag2,Tag3"
"Next line","This is the file description and it can include line breaks

Size: 16x16
Weight: 1,5
for example here

more information.",12.99,USD,10,"Tag1,Tag2,Tag3"

我试图逐行读取这个文件，不幸的是这在 JS 中不起作用。

    const reader = new FileReader();
    reader.onload = async (evt) => {
        const file = evt.target.result.split('\r\n')

当我在 Numbers (Mac = Excel) 中打开文件并通过文件 > 导出 > CSV > 文本编码 Unicode (UTF-8) 保存时，文件的输出如下：

TITLE;DESCRIPTION;PRICE;CURRENCY_CODE;QUANTITY;TAGS
"This is the file title";"This is the file description and it can include line breaks

Size: 16x16
Weight: 1,5
for example here

more information.";12.99;USD;10;"Tag1;Tag2;Tag3"
"Next line";"This is the file description and it can include line breaks

Size: 16x16
Weight: 1,5
for example here

more information.";12.99;USD;10;"Tag1;Tag2;Tag3"
"Next line";"This is the file description and it can include line breaks

Size: 16x16
Weight: 1,5
for example here

more information.";12.99;USD;10;"Tag1;Tag2;Tag3"

我可以很好地处理这种文件格式。正如我所看到的，所有列现在都通过

;

进行标记，并且换行符

evt.target.result.split('\r\n')

也可以工作。

不幸的是，我不能假设我的用户能够转换此文件。

因此，我想像 Numbers 上传文件时那样转换文件。

这是如何通过 JavaScript new FileReader() 工作的？

Answer 1

您可以通过两种方式处理：

1. 前端

安装

PapaParse

npm install papaparse

让浏览器自动转换

csv

:

let fileInput = document.getElementById('csv_file');
fileInput.addEventListener('change', function (event) {
    Papa.parse(fileInput.files[0], {
        download: true,
        delimiter: ",",
        complete: function (results) {
            let csvRows = results.data;
            let newCsvStr = csvRows.map(e => e.join(';')).join('\n')
            console.log(newCsvStr)
        }
    });
});

2. 后端

安装

CsvWriter

npm install --save csv-parser csv-writer

在后端发送到客户端之前转换文件：

const fs = require('fs');
const csv = require('csv-parser');
const createCsvWriter = require('csv-writer').createObjectCsvWriter;

const data = [];

fs.createReadStream('input.csv')
  .pipe(csv({ separator: ',' }))
  .on('data', (row) => {
    data.push(row);
  })
  .on('end', () => {
    let csvWriter = createCsvWriter({
      path: 'output.csv',
      header: Object.keys(data[0]).map(key => ({id: key, title: key}))
    });

    csvWriter.writeRecords(data)
      .then(() => console.log('The CSV file was written successfully'));
  });