30秒学会 JavaScript 片段 – CSV to JSON

Converts a comma-separated values (CSV) string to a 2D array of objects.
The first row of the string is used as the title row.

• Use Array.prototype.indexOf() to find the first newline character (\n).
• Use Array.prototype.slice() to remove the first row (title row) and String.prototype.split() to separate it into values, using the provided delimiter.
• Use String.prototype.split() to create a string for each row.
• Use String.prototype.split() to separate the values in each row, using the provided delimiter.
• Use Array.prototype.reduce() to create an object for each row’s values, with the keys parsed from the title row.
• Omit the second argument, delimiter, to use a default delimiter of ,.

代码实现

const CSVToJSON = (data, delimiter = ',') => {
  const titles = data.slice(0, data.indexOf('\n')).split(delimiter);
  return data
    .slice(data.indexOf('\n') + 1)
    .split('\n')
    .map(v => {
      const values = v.split(delimiter);
      return titles.reduce(
        (obj, title, index) => ((obj[title] = values[index]), obj),
        {}
      );
    });
};

CSVToJSON('col1,col2\na,b\nc,d');
// [{'col1': 'a', 'col2': 'b'}, {'col1': 'c', 'col2': 'd'}];
CSVToJSON('col1;col2\na;b\nc;d', ';');
// [{'col1': 'a', 'col2': 'b'}, {'col1': 'c', 'col2': 'd'}];

翻译自：https://www.30secondsofcode.org/js/s/csv-to-json