I want to create an .xlsx file not .xls using my razor view string, But it doesn't work here is my code
private ContentResult GenerateExcel<T>(string viewName, T model) where T : class
{
var htmlViewRenderer = new HtmlViewRenderer();
string htmlText = htmlViewRenderer.RenderViewToString(this, viewName, model);
// byte[] renderedBuffer;
Response.ClearContent();
Response.Buffer = true;
Response.AddHeader("content-disposition", "attachment; filename=Marklist.xlsx");
Response.ContentType = "application/ms-excel";
Response.Charset = "";
StringWriter sw = new StringWriter();
HtmlTextWriter htw = new HtmlTextWriter(sw);
Response.Output.Write(htmlText.ToString());
Response.Flush();
Response.End();
return Content(htmlText,Response.ContentType);
}