读取上传的CSV为DataTable

csv导入文件会把每列的数据用英文逗号分割开来，如果遇到某列中包含英文逗号，则会把该列用英文双引号进行包装。

如果csv文件中某列的数据本身包含英文逗号,应该使用读取字符串的方式进行解析数据，如csv的数据如下，ReGoodsCode,SKUCode,PlatformCode,GoodsName,GoodsCount,RefundAmount,Phone,MallID,UserName,ReTime
1.56E+14,xg003809216-z,4M天猫旗舰店,"4M ,,高曼",5,500,13907927272,"匿名用户,lisi","张三,xxx,ooo",2014/12/23 14:10

这时应用如下方法进行解析数据，

private IEnumerable<string[]> ExCsv1(string path)
        {
            var sr = File.ReadAllLines(path, System.Text.Encoding.UTF8);
            int i = 0, m = 0;

for (var a = 1; a < sr.Length; a++)
            {
                string[] split = sr[a].Split(',');
                string[] newsplit = new string[split.Length];
                var fix = 0;

for (i = 0; i + fix < split.Length; i++)
                {
                    newsplit[i] = split[i + fix];
                    if (newsplit[i].StartsWith("\"") && !newsplit[i].EndsWith("\""))
                    {
                        for (var j = i + fix + 1; j < split.Length; j++, fix++)
                        {
                            newsplit[i] += "," + split[j];
                            if (split[j].EndsWith("\"")) break;
                        }
                    }
                }
                yield return newsplit;
            }
        }

使用时，

if (FileUpload1.HasFile)
            {
                try
                {
                    //FileUpload1.SaveAs(Server.MapPath("upload") + "\\" + FileUpload1.FileName);
                    //这里永远只保存一个文件
                    string path = ConfigurationManager.AppSettings["ReturnGoodsPath"];
                    FileUpload1.SaveAs(path + FileUpload1.FileName);
                    var dt = ExCsv1(path + FileUpload1.FileName);
                    //DataTable dt = csv2dt(path + FileUpload1.FileName, 1);
                    //var codeisInt = dt.Columns[0].DataType == typeof(int) || dt.Columns[0].DataType == typeof(double);

//绑定数据源
                    //GridView1.DataSource = dt;
                    //GridView1.DataBind();

var msg = "客户端路径：" + FileUpload1.PostedFile.FileName + "<br>" +
                    "文件名：" + System.IO.Path.GetFileName(FileUpload1.FileName) + "<br>" +
                    "文件扩展名：" + System.IO.Path.GetExtension(FileUpload1.FileName) + "<br>" +
                    "文件大小：" + FileUpload1.PostedFile.ContentLength + " KB<br>" +
                    "文件MIME类型：" + FileUpload1.PostedFile.ContentType + "<br>" +
                    "保存路径：" + Server.MapPath("upload") + "\\" + FileUpload1.FileName;

List<ReOrder> r = new List<ReOrder>();
                    foreach (var item in dt)
                    {
                        string orderCode = item[0].ToString();// codeisInt ? ((double)item[0]).ToString("D") : item[0].ToString();
                        string productCode = item[1].ToString();
                        ReOrder ord = r.Where(t => t.Code == orderCode).FirstOrDefault();

if (ord == null)
                        {
                            ord = new ReOrder();
                            ReOrderDetail det = new ReOrderDetail();

ord.Code = orderCode;// item[0].ToString();
                            det.SKUCODE = item[1].ToString();
                            ord.PlatformCode = item[2].ToString();
                            det.GoodsName = item[3].ToString();
                            det.GoodsCount = int.Parse(item[4].ToString());
                            ord.TotalAmount = decimal.Parse(item[5].ToString());
                            det.TotalAmount = decimal.Parse(item[5].ToString());
                            ord.phone = item[6].ToString();
                            ord.MallID = item[7].ToString();
                            ord.UserName = item[8].ToString();
                            ord.ReGoodsTime = DateTime.Parse(item[9].ToString());
                            ord.ReOrderDetails.Add(det);
                            r.Add(ord);
                        }
                        else if (!ord.ReOrderDetails.Any(d => d.SKUCODE == productCode))
                        {
                            ReOrderDetail det = new ReOrderDetail();
                            det.SKUCODE = item[1].ToString();
                            det.GoodsName = item[3].ToString();
                            det.GoodsCount = int.Parse(item[4].ToString());
                            det.TotalAmount = decimal.Parse(item[5].ToString());
                            ord.TotalAmount = ord.TotalAmount + decimal.Parse(item[5].ToString());
                            ord.ReOrderDetails.Add(det);
                        }
                    }

var returnGoodsGroups = r.GroupBy(x => x.phone).ToArray();

foreach (var item in returnGoodsGroups)
                    {

LogEntry entry = new LogEntry("返回退货", 1);
                        LogStub.Log(entry);
                        var res = await LogicStub.ReturnGoodsHandler.HandleReturnGoods(new SDK.ReturnGoodsInfo
                           {
                               Orders = item.ToList(),
                               MemberKeyValue = item.Key
                           });
                        msg += "<br/>" + res;// == "{}" ? "<br/>OK!" : "<br/>" + res;

}
                    Label1.Text = msg;
                }
                catch (Exception ex)
                {
                    Label1.Text = "发生错误：" + ex.Message.ToString();
                }
            }

也可以使用以下方法获取数据，但此方法可能无法解决列数据中包含英文逗号的问题：

/// <summary>
        /// CSV文件转换
        /// 作为数据源
        /// </summary>
        /// <returns></returns>
        private DataTable ExCsv(string path)
        {
            // csv file:HDR=Yes-- first line is header
            string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + path
                + ";Extended Properties='TEXT;HDR=Yes;FMT=Delimited;CharacterSet=65001;'";
            OleDbConnection oleConn = new OleDbConnection(strConn);
            oleConn.Open();
            DataTable sheets = oleConn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
            DataTable dt = new DataTable();
            if (sheets != null && sheets.Rows.Count > 0)
            {
                String fileName = sheets.Rows[0]["TABLE_NAME"].ToString(); // sheets.Rows[0] -- first sheet of excel 
                string olestr = "select * from [" + fileName + "]";
                OleDbCommand oleComm = new OleDbCommand(olestr, oleConn);
                oleComm.Connection = oleConn;
                OleDbDataAdapter oleDa = new OleDbDataAdapter();
                oleDa.SelectCommand = oleComm;
                oleDa.Fill(dt);
                oleConn.Close();
            }
            return dt;
        }

调用时，

if (FileUpload1.HasFile)
            {
                    //FileUpload1.SaveAs(Server.MapPath("upload") + "\\" + FileUpload1.FileName);
                    //这里永远只保存一个文件
                    string path = ConfigurationManager.AppSettings["ReturnGoodsPath"];
                    FileUpload1.SaveAs(path + FileUpload1.FileName);
                    DataTable dt = ExCsv(path);

//绑定数据源
                    //GridView1.DataSource = dt;
                    //GridView1.DataBind();

Label1.Text = "客户端路径：" + FileUpload1.PostedFile.FileName + "<br>" +
                    "文件名：" + System.IO.Path.GetFileName(FileUpload1.FileName) + "<br>" +
                    "文件扩展名：" + System.IO.Path.GetExtension(FileUpload1.FileName) + "<br>" +
                    "文件大小：" + FileUpload1.PostedFile.ContentLength + " KB<br>" +
                    "文件MIME类型：" + FileUpload1.PostedFile.ContentType + "<br>" +
                    "保存路径：" + Server.MapPath("upload") + "\\" + FileUpload1.FileName;

}