title: Exporting an array to excel file with cell formatting
body: <p>I'm currently trying to export an array to an excel file with cell formatting.</p>
  
  <p>I'm starting off with this code here:</p>
  
  <pre><code>https://github.com/SheetJS/js-xlsx/blob/master/tests/write.js
  </code></pre>
  
  <p>But the problem is that whenever I'm trying to export it (save the file as an xlsx file) this is the error that shows up in the console:</p>
  
  <pre><code>Uncaught TypeError: Cannot read property 'writeFileSync' of undefined    xlsx.js:5182 
  writeSync                 xlsx.js:5182 
  writeFileSync             xlsx.js:5173 
  process_xlsx              Test.html:379 
  reader.onload             Test.html:438 
  </code></pre>
  
  <p>The last 2 lines are basically the part of the code which says</p>
  
  <pre><code>XLSX.writeFile(wb, 'sheetjs.xlsx');
  </code></pre>
  
  <p>I know wb is not undefined as if I try and do console.log of it, the excel spreadsheet shows up properly :|</p>
  
  <p>Can someone help me with this? I'm also trying to have each cell have a different formatting (IE different color/bolded/filled/etc)</p>