import excel to datatable

之前在網路上查到的，臨時找不回那篇文章，只留當初找到的那個檔案
直接下載這個專案檔去試試看就知道了~
點我下載 ImportExcelData.zip

將excel資料匯入datatable中

主功能程式碼如下

            if (FileUpload1.HasFile)
            {
                string connectionstring = "";
                string filename = Path.GetFileName(FileUpload1.PostedFile.FileName);
                string fileextension = Path.GetExtension(FileUpload1.PostedFile.FileName);
                string filelocation = Server.MapPath("~/file/") + filename;
                FileUpload1.SaveAs(filelocation);
                if (fileextension == ".xlsx")
                {
                    connectionstring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + filelocation + ";Extended Properties=\"Excel 12.0;HDR=YES;IMEX=2\"";
                    OleDbConnection conn = new OleDbConnection(connectionstring);
                    OleDbCommand cmd = new OleDbCommand();
                    cmd.CommandType = System.Data.CommandType.Text;
                    cmd.CommandText = "select * from [Sheet1$]";
                    cmd.Connection = conn;
                    OleDbDataAdapter oda = new OleDbDataAdapter(cmd);
                    System.Data.DataTable dt = new System.Data.DataTable();
                    oda.Fill(dt);
                    Gridview1.DataSource = dt;
                    Gridview1.DataBind();
                }
            }
            else
            {
                BtnUpload.Attributes.Add("OnClientClick", "javascript:alert('Select Excel file');");
                Gridview1.DataSource = null;
                Gridview1.DataBind();
            }
            FileUpload1.Attributes.Clear();