save file on loacal machine dialog in mvc
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Hi all wondering if someone can help; i've written this code which will generate an CSV file spreadsheet and save it to a specified location. I want to then display a "Save as" dialogue box by reading the file from the stored location and then asking then user where they want to store it. The excel file is not generated and after click on action link "Export To CSV"  in next window it will show undefined  as a massege! However my problem is the code i've written seems to be outputting the file directly to my browser, so i get all the contents of the CSV file on my browser screen, not displaying the save as dialogue box as expected!

Here is my Code

  public ActionResult ExportToCSSReport(List<CEPMobility.CEPServiceProxy.CSSReport>  Report) 
        {
            MemoryStream output = new MemoryStream(); 
            StreamWriter writer = new StreamWriter(output, System.Text.Encoding.UTF8);
            writer.WriteLine("PROJECT NAME,CSS ID,CSS Name,Customer Reprentative Name,CSS Recived Date,CSI,TOP 3 STRENGTH,TOP 3 OFI,Any Other COMMENT");
            foreach (CEPMobility.CEPServiceProxy.CSSReport objreport in Report)
            {
                writer.WriteLine("\"" + objreport.PROJECT_NAME + "\",\"" + objreport.CSS_ID + "\",\"" + objreport.CSS_NAME + "\",\"" + objreport.CUST_REP_NAME + "\",\"" + objreport.CSS_RECIEVED_DT + "\",\"" + objreport.CSI + "\",\"" + objreport.TOP_3_STRENGTH + "\",\"" + objreport.TOP_3_OFI + "\",\"" + objreport.COMMENT + "\""); 
            } 
            writer.Flush(); 
            output.Seek(0, SeekOrigin.Begin);
            return File(output, "text/csv", "CSSReport.csv"); 
        }         
      
