JS: CSV File Creation Using BLOB

jsCSVFileCreationBlob.js

function exportToCsv(filename, rows) {
        var processRow = function (row) {
            var finalVal = '';
            for (var j = 0; j < row.length; j++) {
                var innerValue = row[j] === null ? '' : row[j].toString();
                if (row[j] instanceof Date) {
                    innerValue = row[j].toLocaleString();
                };
                var result = innerValue.replace(/"/g, '""');
                if (result.search(/("|,|\n)/g) >= 0)
                    result = '"' + result + '"';
                if (j > 0)
                    finalVal += ',';
                finalVal += result;
            }
            return finalVal + '\n';
        };

        var csvFile = '';
        for (var i = 0; i < rows.length; i++) {
            csvFile += processRow(rows[i]);
        }

        var blob = new Blob([csvFile], { type: 'text/csv;charset=utf-8;' });
        if (navigator.msSaveBlob) { // IE 10+
            navigator.msSaveBlob(blob, filename);
        } else {
            var link = document.createElement("a");
            if (link.download !== undefined) { // feature detection
                // Browsers that support HTML5 download attribute
                var url = URL.createObjectURL(blob);
                link.setAttribute("href", url);
                link.setAttribute("download", filename);
                link.style.visibility = 'hidden';
                document.body.appendChild(link);
                link.click();
                document.body.removeChild(link);
            }
        }
    }

how to force user to save file on desktop only rather than in download folder ?

how to force user to save file on desktop only rather than in download folder ?

The download destination is determined by the user's browser preferences only. This could be different between users and you cannot control this with JavaScript.

Can you please provide an example for an input? for the rows variable?
Thanks!

I created a csv from an object like this:

const csvData = data.reduce((prev, curr) => (prev += Object.values(curr).join(Delimiter) + "\n"), "");

const Delimiter = ","
and csvData is an array of objects.

You need to add headers too,
and then join csvData with csvHeaders with a delimiter.

const csv = `${csvHeaders}\n${csvData}`;

csvHeaders can be Object.keys(data[0]).join(Delimiter);

Don't forget to call URL.revokeObjectURL at the end.

Don't forget to call URL.revokeObjectURL at the end.

Why?

revokeObjectURL

Memory management is a thing.

https://developer.mozilla.org/en-US/docs/Web/API/URL/revokeObjectURL_static

"Call this method when you've finished using an object URL to let the browser know not to keep the reference to the file any longer."