how to loop through a csv file row by row and then cell by cell in javascript

To loop through a CSV file row by row and then cell by cell in JavaScript, you can use the built-in FileReader class to read the contents of the file and then split it into rows and cells using the split() method. Here's an example:

index.tsx
let fileInput = document.getElementById('fileInput');

fileInput.addEventListener('change', (event) => {
  let file = event.target.files[0];
  let reader = new FileReader();

  reader.readAsText(file);

  reader.onload = () => {
    let rows = reader.result.split('\n');
    rows.forEach((row) => {
      let cells = row.split(',');
      cells.forEach((cell) => {
        // do something with each cell
        console.log(cell.trim());
      });
    });
  };
});
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In this example, we first get the file input element and add an event listener for the "change" event. When the user selects a file, we create a new FileReader object and use its readAsText() method to read the contents of the file.

Once the file has been read, we split it into rows using the split() method with the newline character as the delimiter. We then loop through each row and split it into cells using the split() method with the comma character as the delimiter.

Finally, we loop through each cell and do something with it, such as logging its value to the console.