Import .csv file into oracle database.

Question

my csv file contain a column which is having a date datatype and im getting an error which is row1 column 1 is invalid number.How to resolve this problem.The code is written in asp.net and c#

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.OleDb;
using System.Data.SqlTypes;
using System.Globalization;
using System.IO;
//using System.Data.OracleClient;
using Oracle.DataAccess.Client;
public partial class Exp : System.Web.UI.Page
{
public OleDbConnection conn = new OleDbConnection(ConfigurationManager.ConnectionStrings["conguest"].ToString());
public OracleConnection conn1 = new OracleConnection(ConfigurationManager.ConnectionStrings["conguest1"].ToString());
private void InsertCSVRecords(DataTable dt)
{
conn1.Open();
OracleBulkCopy OracleBulkCopy = new OracleBulkCopy(conn1);
OracleBulkCopy.DestinationTableName = "guest.material_master";
//Response.Write("test2");
OracleBulkCopy.ColumnMappings.Add("REQ_NO", "REQ_NO");
OracleBulkCopy.ColumnMappings.Add("REQ_DT", "REQ_DT");
OracleBulkCopy.ColumnMappings.Add("REQ_BY", "REQ_BY");
OracleBulkCopy.ColumnMappings.Add("MAT_CD", "MAT_CD");
OracleBulkCopy.ColumnMappings.Add("MAT_DESC", "MAT_DESC");
OracleBulkCopy.ColumnMappings.Add("MAT_TYPE_CD", "MAT_TYPE_CD");
OracleBulkCopy.ColumnMappings.Add("BASE_UOM_CD", "BASE_UOM_CD");
OracleBulkCopy.ColumnMappings.Add("STOR_LOC_CD", "STOR_LOC_CD");
OracleBulkCopy.ColumnMappings.Add("PUR_GRP_CD", "PUR_GRP_CD");
OracleBulkCopy.ColumnMappings.Add("HSN_CD", "HSN_CD");
OracleBulkCopy.ColumnMappings.Add("MAT_LONG_DESC", "MAT_LONG_DESC");
OracleBulkCopy.ColumnMappings.Add("TAX_IND", "TAX_IND");
OracleBulkCopy.ColumnMappings.Add("ACTIVE_IND", "ACTIVE_IND");
OracleBulkCopy.ColumnMappings.Add("DEL_IND", "DEL_IND");
OracleBulkCopy.WriteToServer(dt);
conn1.Close();
}
protected void Button4_Click(object sender, EventArgs e)
{
//try
//{
string csvPath = Server.MapPath("~/Uploads/") + Path.GetFileName(FileUpload1.PostedFile.FileName);
FileUpload1.SaveAs(csvPath);
if ((FileUpload1.PostedFile != null) && (FileUpload1.PostedFile.ContentLength > 0))
{
string fn = System.IO.Path.GetFileName(FileUpload1.PostedFile.FileName);
string SaveLocation = Server.MapPath("~/Uploads") + "\\" + fn;
FileUpload1.PostedFile.SaveAs(SaveLocation);
Response.Write("The file has been uploaded.");
DataTable dt = new DataTable();
//DataSet ds = new DataSet();
dt.Columns.AddRange(new DataColumn[14] {
new DataColumn("REQ_NO", typeof(string)),
new DataColumn("REQ_DT", typeof(string)),
new DataColumn("REQ_BY",typeof(string)),
new DataColumn("MAT_CD", typeof(string)),
new DataColumn("MAT_DESC", typeof(string)),
new DataColumn("MAT_TYPE_CD", typeof(string)),
new DataColumn("BASE_UOM_CD", typeof(string)),
new DataColumn("STOR_LOC_CD", typeof(string)),
new DataColumn("PUR_GRP_CD", typeof(string)),
new DataColumn("HSN_CD", typeof(string)),
new DataColumn("MAT_LONG_DESC", typeof(string)),
new DataColumn("TAX_IND", typeof(string)),
new DataColumn("ACTIVE_IND", typeof(string)),
new DataColumn("DEL_IND", typeof(string))});
//DateTime dt1 = DateTime.Parse("dd-MMM-yyyy");
string csvData = File.ReadAllText(fn);
foreach (string row in csvData.Split('\r'))
{
if (!string.IsNullOrEmpty(row))
{
dt.Rows.Add();
int i = 0;
foreach (string cell in row.Split(','))
{
dt.Rows[dt.Rows.Count - 1][i] = cell;
i++;
}
}
}
GridView1.DataSource = dt;
GridView1.DataBind();
//Response.Write("Test2");
InsertCSVRecords(dt);
}
else
{
Response.Write("Please select a file to upload.");
}
//}
//catch (Exception ex)
//{
// Response.Write(ex.Message);
//}
}
}