Javascript - Download CSV as File

function downloadFile(fileName, urlData) {

    var aLink = document.createElement('a');
    var evt = document.createEvent("HTMLEvents");
    evt.initEvent("click");
    aLink.download = fileName;
    aLink.href = urlData;
    aLink.dispatchEvent(evt);
}

var data = '"Column One","Column Two","Column Three"';
downloadFile('2.csv', 'data:text/csv;charset=UTF-8,' + encodeURIComponent(data));

http://jsfiddle.net/rooseve/7bUG8/

In my case, it turned out that Excel ignored the charset=UTF-8 part. I found a solution in this post, to force Excel to take into account the UTF-8. So this last line did the trick for me:

downloadFile('2.csv', 'data:text/csv;charset=UTF-8,' + '\uFEFF' + encodeURIComponent(data));

Updated Andrew's Answer to avoid using a deprecated function.

source: https://developer.mozilla.org/en-US/docs/Web/Guide/Events/Creating_and_triggering_events#The_old-fashioned_way

//Triggers a download of the given file
//@see https://stackoverflow.com/questions/21177078/javascript-download-csv-as-file
//@see https://developer.mozilla.org/en-US/docs/Web/Guide/Events/Creating_and_triggering_events#The_old-fashioned_way
//
//@param fileName {string} - Name of the file to download include file extension
//@param urlData {string} - Encoded URI of the document data
function downloadFile(fileName, urlData) {

    var aLink = document.createElement('a');
    aLink.download = fileName;
    aLink.href = urlData;

    var event = new MouseEvent('click');
    aLink.dispatchEvent(event);
}

var data = '"Column One","Column Two","Column Three"';
downloadFile('2.csv', 'data:text/csv;charset=UTF-8,' + encodeURIComponent(data));