ASP.NETでCSV出力

protected void Page_Load(object sender, EventArgs e)
{
  System.Text.Encoding encoding = System.Text.Encoding.GetEncoding("Shift-JIS");

  Response.AddHeader("Content-Disposition", "attachment;filename=date.csv");  //ファイル名
  Response.ContentType = "application/octet-stream";
  Response.ContentType = "text/csv";

  string csvbody="ID,Date,Name,Price";
  csvbody += "\n1,2010/01/01,山田,10000";

  Response.BinaryWrite(encoding.GetBytes(csvbody));
  Response.Write(csvbody);
  Response.End();
}