Export data to excel with EPPlus and WebApi - asp.net-mvc

Question

I'm trying to export a list, but when i open the file download it just shows a bunch of characteres that don't make sense (kinda looks like machine language). I've looked at some codes here and all of them are similar to mine, what am I missing?
Here's my code:
The method I call:
[HttpGet]
public HttpResponseMessage Get()
{
HttpResponseMessage response;
response = Request.CreateResponse(HttpStatusCode.OK);
MediaTypeHeaderValue mediaType = new MediaTypeHeaderValue("application/ms-excel");
response.Content = new StreamContent(GetExcelSheet());
response.Content = response.Content;
response.Content.Headers.ContentType = mediaType;
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
response.Content.Headers.ContentDisposition.FileName = "PivotGrid_Orders.xls";
return response;
}
The method that format cells:
public MemoryStream GetExcelSheet()
{
using (var package = new ExcelPackage())
{
var worksheet = package.Workbook.Worksheets.Add("Orders");
//worksheet.Cells["A1"].LoadFromCollection()
worksheet.Cells["A1"].LoadFromCollection(Orders(), false);
package.Save();
var stream = new MemoryStream(package.GetAsByteArray()); //capacidade
return stream;
}
}
The list i've created to test:
public List<ExListModel> Orders()
{
List<ExListModel> lst = new List<ExListModel>();
orders.Add(new ExListModel{ Nome = "Developer"});
return lst;
}

Answer 1

As I didn't know EPPlus, I googled it, and its Github page states it produces Open XML excel files (.xlsx). You produce the file with an extension and mimetype of the old binary excel filetype. Change the contenttype to application/vnd.openxmlformats-officedocument.spreadsheetml.sheet and the filename extension to xlsx.