comment importer les données à partir d'une feuille excel dans la table sql server?

Salut. Je veux importer la feuille excel de données vers SQL server le tableau,pour qui j'ai écrit le code comme ci-dessous. La feuille est de les télécharger dans le dossier,mais les données ne sont pas importés à la table,quelqu'un peut-il me dire s'il vous plaît où est l'erreur....

public partial class upload2 : System.Web.UI.Page
{
private string connStr = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
PopulateDatabaseTables();
}
}
private void PopulateDatabaseTables()
{
string tableName = string.Empty;
string sql = "SELECT *, name AS table_name " +
" FROM sys.tables WHERE Type = 'U' ORDER BY table_name";
using (SqlConnection conn = new SqlConnection(connStr))
{
using (DataTable table = new DataTable())
{
conn.Open();
using (SqlDataAdapter dAd = new SqlDataAdapter(sql, conn))
{
dAd.Fill(table);
}
ListBox1.DataSource = table;
ListBox1.DataBind();
}
}
}
protected void ImportNow_Click(object sender, EventArgs e)
{
if (ListBox1.SelectedValue == "")
{
lblMessage.ForeColor = Color.Red;
lblMessage.Text = "Please select table in which you want to import data from excel sheet";
}
else if ((fileuploadExcel.FileName != ""))
{
string extension = Path.GetExtension(fileuploadExcel.PostedFile.FileName);
string excelConnectionString;
SqlConnection conn = new SqlConnection(connStr);
string tableName = ListBox1.SelectedValue;
//string path = fileuploadExcel.PostedFile.FileName;
string path = Server.MapPath("~/fileuploadExcel/" + fileuploadExcel.FileName);
fileuploadExcel.SaveAs(path);
Response.Write("path=" + path);
return;
//Create connection string to Excel work book
if (extension == ".xlsx")
{
excelConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=+ path +
;Extended Properties=Excel 8.0;Persist Security Info=False";
}
else
{
excelConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;sData Source= + path +
;Extended Properties=Excel 12.0;Persist Security Info=False";
}
//Create Connection to Excel work book
SqlConnection excelConnection = new SqlConnection(excelConnectionString);
//Create OleDbCommand to fetch data from Excel             
conn.Open();
SqlCommand comm = new SqlCommand("truncate table " + tableName, conn);
SqlCommand identityChange = conn.CreateCommand();
identityChange.CommandText = "SET IDENTITY_INSERT " + tableName + " ON";
SqlCommand cmd = new SqlCommand("Select * from [Sheet1$]", excelConnection);
excelConnection.Open();
SqlDataReader dReader;
dReader = cmd.ExecuteReader();
identityChange.ExecuteNonQuery();
SqlBulkCopy sqlBulk = new SqlBulkCopy(connStr);
//Give your Destination table name
sqlBulk.DestinationTableName = tableName;
sqlBulk.WriteToServer(dReader);
excelConnection.Close();
conn.Close();
lblMessage.ForeColor = Color.Green;
lblMessage.Text = "Import into table <b>" + tableName + "</b> successful!<br />";
}
else
{
lblMessage.ForeColor = Color.Red;
lblMessage.Text = "Please first upload (Select) excel file.";
}
}
protected void viewdata_Click(object sender, EventArgs e)
{
BindData();
}
private void BindData()
{
try
{
if (ListBox1.SelectedValue == "")
{
lblMessage.ForeColor = Color.Red;
lblMessage.Text = "Please select table for which you want to view data in Gridview";
}
else
{
string tableName = ListBox1.SelectedValue;
SqlConnection conn = new SqlConnection(connStr);
SqlDataAdapter sda = new SqlDataAdapter("select * from " + tableName, conn);
DataSet ds = new DataSet();
sda.Fill(ds);
gvdetails.DataSource = ds;
gvdetails.DataBind();
}
}
catch (DataException de)
{
lblMessage.Text = de.Message;
lblMessage.ForeColor = System.Drawing.Color.Red;
}
}
protected void gvdetails_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
gvdetails.PageIndex = e.NewPageIndex;
BindData();
}
}
}