مساعده فى تعديل على كود اللغه العربيه تظهر علامات استفهام او علامات غير مغهومه

using System; 
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using MySql.Data.MySqlClient;
using System.Configuration;
using System.IO;

Function for exporting to Excel:

private void ToCsV(DataGridView dGV, string filename)        {            string stOutput = "";            // Export titles:            string sHeaders = "";            for (int j = 0; j < dGV.Columns.Count; j++)                sHeaders = sHeaders.ToString() + Convert.ToString(dGV.Columns[j].HeaderText) + "\t";            stOutput += sHeaders + "\r\n";            // Export data.            for (int i = 0; i < dGV.RowCount - 1; i++)            {                string stLine = "";                for (int j = 0; j < dGV.Rows.Cells.Count; j++)                    stLine = stLine.ToString() + Convert.ToString(dGV.Rows.Cells[j].Value) + "\t";                stOutput += stLine + "\r\n";            }            Encoding utf16 = Encoding.GetEncoding(1254);            byte[] output = utf16.GetBytes(stOutput);            FileStream fs = new FileStream(filename, FileMode.Create);            BinaryWriter bw = new BinaryWriter(fs);            bw.Write(output, 0, output.Length); //write the encoded file            bw.Flush();            bw.Close();            fs.Close();        }

Code for button for exporting to Excel

    SaveFileDialog sfd = new SaveFileDialog();
            sfd.Filter = "Excel Documents (*.xls)|*.xls";
            sfd.FileName = "export.xls";
            if (sfd.ShowDialog() == DialogResult.OK)
            {
                //ToCsV(dataGridView1, @"c:\export.xls");
                ToCsV(dataGridView1, sfd.FileName); // Here dataGridview1 is your grid view name 
            }

انا اعلم ان المشكله فى ترميز اللغه العربيه

Encoding utf16

لكن لا اعلم الترميز الصحيح 

تحياتى وكل عام وانتم بخير