Export hindi data to excel from datatable in ASP.NET?

public void ExportToExcel(DataTable dt)
{
    Response.ClearContent();
    Response.Buffer = true;
    Response.AddHeader("content-disposition", string.Format("attachment; filename={0}", "Customers.xls"));
    Response.ContentType = "application/ms-excel";
    Response.ContentEncoding = System.Text.Encoding.UTF8;
    Response.Charset = "";
    DataTable dt1 = dt;
    string str = string.Empty;
    foreach (DataColumn dtcol in dt1.Columns)
    {
        Response.Write(str + dtcol.ColumnName);
        str = "\t";
    }
    Response.Write("\n");
    foreach (DataRow dr in dt1.Rows)
    {
        str = "";
        for (int j = 0; j < dt1.Columns.Count; j++)
        {
            Response.Write(str + Convert.ToString(dr[j]));
            str = "\t";
        }
        Response.Write("\n");
    }
    Response.End();
}