I have a simple web application that is reading records from a CSV file and storing them in a database table. Then I am using SqlBulkCopy to copy the records into an SQL database using batches. All is fine with the insert. I am trying to give the user some feedback using OnSqlRowsCopied and NotifyAfter. The goal is to update a label that is contained in an UpdatePanel to display the number of records copied at the current NotifyAfter interval. However, the label will not update until SqlBulkCopy has complete. I can see that the s_OnSqlRowsCopied event is firing using Debug.WriteLine. What is the reason why the label won't update and how can I overcome this?
Code Behind
Imports System.Data.SqlClient
Public Class WebForm1
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
End Sub
Dim filePath As String
Dim rowsCopied As String
Public Sub btnGetCSV_Click(sender As Object, e As EventArgs) Handles btnGetCSV.Click
filePath = System.IO.Path.GetFullPath(fileUpload1.PostedFile.FileName)
lblInfo.Text = filePath
End Sub
Protected Sub btnToSQL_Click(sender As Object, e As EventArgs) Handles btnToSQL.Click
Dim cs As String = System.Web.Configuration.WebConfigurationManager.ConnectionStrings("csMediaPortal").ConnectionString
CopyData(CSVtoDataTable(lblInfo.Text.ToString()), cs)
End Sub
Private Function CSVtoDataTable(filePath As String) As DataTable
Dim dt As DataTable = Nothing
Dim sourcePath As String = String.Empty
Dim csvFile As String = String.Empty
Dim conString As String = String.Empty
Dim conn As OleDb.OleDbConnection = Nothing
Dim adapter As OleDb.OleDbDataAdapter = Nothing
Dim selString As String = String.Empty
Try
sourcePath = System.IO.Path.GetDirectoryName(filePath)
csvFile = System.IO.Path.GetFileName(filePath)
conString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & sourcePath & ";Extended Properties=""text;HDR=No;FMT=FixedLength"""
conn = New OleDb.OleDbConnection(conString)
selString = "Select * From " & csvFile
adapter = New OleDb.OleDbDataAdapter(selString, conn)
dt = New DataTable(System.IO.Path.GetFileNameWithoutExtension(filePath))
conn.Open()
adapter.Fill(dt)
conn.Close()
Catch ex As Exception
lblInfo.Text = ex.Message
Finally
adapter.Dispose()
conn.Dispose()
End Try
Return dt
End Function
Protected Sub CopyData(sourceTable As DataTable, cs As String)
Using s As SqlBulkCopy = New SqlBulkCopy(cs, SqlBulkCopyOptions.UseInternalTransaction)
s.DestinationTableName = "test"
s.BatchSize = 1000
Try
AddHandler s.SqlRowsCopied, AddressOf s_OnSqlRowsCopied
s.NotifyAfter = 900
s.WriteToServer(sourceTable)
Catch ex As Exception
DirectCast(DirectCast(HttpContext.Current.Handler, Page).FindControl("lblInfo"), Label).Text = "Commit Error: " & ex.Message
End Try
s.Close()
End Using
End Sub
Protected Sub s_OnSqlRowsCopied(sender As Object, e As SqlRowsCopiedEventArgs)
Me.lblProgress.Value = e.RowsCopied.ToString()
Me.UpdatePanel1.Update()
Debug.WriteLine(e.RowsCopied)
End Sub
End Class
Web Form
<%@ Page Language="vb" CodeBehind="WebForm1.aspx.vb" Inherits="CSVUpload.WebForm1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<div>
<asp:FileUpload ID="fileUpload1" runat="server" />
<asp:Button ID="btnGetCSV" runat="server" Text="Post" OnClick="btnGetCSV_Click" />
<asp:Label ID="lblInfo" runat="server" Text="Label"></asp:Label>
</div>
<asp:Button ID="btnToSQL" runat="server" Text="Insert To SQL" OnClick="btnToSQL_Click" />
<div>
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<input runat="server" type="text" id="lblProgress" value="0" />
</ContentTemplate>
</asp:UpdatePanel>
</div>
</form>
</body>
</html>
