How to save .xlsx data to file as a blob

Question

I have a similar question to this question(Javascript: Exporting large text/csv file crashes Google Chrome):

I am trying to save the data created by excelbuilder.js's EB.createFile() function. If I put the file data as the href attribute value of a link, it works. However, when data is big, it crashes Chrome browser. Codes are like this:

//generate a temp <a /> tag var link = document.createElement("a"); link.href = 'data:application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;base64,' + encodeURIComponent(data); link.style = "visibility:hidden"; link.download = fileName;  document.body.appendChild(link); link.click(); document.body.removeChild(link); 

My codes to create the data using excelbuilder.js is like follows:

var artistWorkbook = EB.createWorkbook(); var albumList = artistWorkbook.createWorksheet({name: 'Album List'});  albumList.setData(originalData);   artistWorkbook.addWorksheet(albumList);  var data = EB.createFile(artistWorkbook); 

As suggested by the answer of the similar question (Javascript: Exporting large text/csv file crashes Google Chrome), a blob needs to be created.

My problem is, what is saved in the file isn't a valid Excel file that can be opened by Excel. The codes that I use to save the blob is like this:

var blob = new Blob(     [data],     {type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;base64,"} );  // Programatically create a link and click it: var a = document.createElement("a"); a.href = URL.createObjectURL(blob); a.download = fileName; a.click(); 

If I replace the [data] in the above codes with [Base64.decode(data)], the contents in the file saved looks more like the expected excel data, but still cannot be opened by Excel.

Thanks!

Answer 1

I had the same problem as you. It turns out you need to convert the Excel data file to an ArrayBuffer.

var blob = new Blob([s2ab(atob(data))], {     type: '' });  href = URL.createObjectURL(blob); 

The s2ab (string to array buffer) method (which I got from https://github.com/SheetJS/js-xlsx/blob/master/README.md) is:

function s2ab(s) {   var buf = new ArrayBuffer(s.length);   var view = new Uint8Array(buf);   for (var i=0; i!=s.length; ++i) view[i] = s.charCodeAt(i) & 0xFF;   return buf; }