Writing CSV files

stackoverflow

How to export JavaScript array info to csv (on client side)? - Stack Overflow

const rows = [
    ["name1", "city1", "some other info"],
    ["name2", "city2", "more info"]
];
 
let csvContent = "data:text/csv;charset=utf-8,";
 
rows.forEach(function(rowArray) {
    let row = rowArray.join(",");
    csvContent += row + "\r\n";
});

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);
        }
    }
}

code-maven

Create and download data in CSV format using plain JavaScript

var data = [
  ['Foo', 'programmer'],
  ['Bar', 'bus driver'],
  ['Moo', 'Reindeer Hunter']
];
 
function download_csv() {
     var csv = 'Name,Title\n';
     data.forEach(function(row) {
             csv += row.join(',');
             csv += "\n";
     });
 
     console.log(csv);
     var hiddenElement = document.createElement('a');
     hiddenElement.href = 'data:text/csv;charset=utf-8,' + encodeURI(csv);
     hiddenElement.target = '_blank';
     hiddenElement.download = 'people.csv';
     hiddenElement.click();
}