I'm trying to implement a direct upload of videos on my server to YouTube. When a user adds a video, it gets copied to YouTube.
The user action of adding the video should begin the upload process, which could take a while. The form, even an asynchronous form, should not sit there and wait for this to happen. It should just begin and allow the user to move on, trusting that it is being taken care of in the background.
To allow this, I am attempting to use system.threading.backgroundworker. My hope is that the process would begin, and the web app would move on. It's not. It's hanging, whether it's an asynchronous or full postback, and waiting for the upload to finish before returning and updating the lblmsg.text.
Is there a different way I should be going about this, so the user can initiate the upload procedure and not wait around for it to complete? Here is my code so far:
Sub up_load(s As Object, e As EventArgs)
Dim worker As BackgroundWorker = New BackgroundWorker
worker.WorkerReportsProgress = True
worker.WorkerSupportsCancellation = True
AddHandler (worker.DoWork), AddressOf begin_upload
'call this and move on?
worker.RunWorkerAsync()
lblmsg.Text = "Successfully initiated upload"
End Sub
Sub begin_upload(s As Object, e As DoWorkEventArgs)
Dim request As New YouTubeRequest(settings)
Dim vidupload As New Video()
vidupload.Title = "My Big Test Movie"
vidupload.Tags.Add(New MediaCategory("Nonprofit", YouTubeNameTable.CategorySchema))
vidupload.Keywords = "church, jesus"
vidupload.Description = "See the entire video"
vidupload.YouTubeEntry.Private = False
vidupload.YouTubeEntry.setYouTubeExtension("location", "Downers Grove, IL")
vidupload.YouTubeEntry.MediaSource = New MediaFileSource("c:\users\greg\test3.asf", "video/x-ms-wmv")
Dim createdVideo As Video = Request.Upload(vidupload)
End Sub
You might want to look into the Task Parallel Library for adding multithreading to your code. Given the code that you provided:
Add this import statement
Imports System.Threading.Tasks
And replace all backgroundworker logic with this simple statement:
Dim uploadTask As Task = Task.Factory.StartNew(Sub()
Dim request As New YouTubeRequest(settings)
Dim vidupload As New Video()
vidupload.Title = "My Big Test Movie"
vidupload.Tags.Add(New MediaCategory("Nonprofit", YouTubeNameTable.CategorySchema))
vidupload.Keywords = "church, jesus"
vidupload.Description = "See the entire video"
vidupload.YouTubeEntry.Private = False
vidupload.YouTubeEntry.setYouTubeExtension("location", "Downers Grove, IL")
vidupload.YouTubeEntry.MediaSource = New MediaFileSource("c:\users\greg\test3.asf", "video/x-ms-wmv")
Dim createdVideo As Video = request.Upload(vidupload)
End Sub)
Now you have the uploadTask uploading your video in the background and your UI thread will be free to process other code. It does get a bit more complicated if you want cancellation and progress reporting, but the link at the top should get you started.
Related
Here is the code, but the datatable is NULL in ButtonExport click event, how can i pass the DataTable to Sub ButtonExport_Click ? I dont want to store in Session as the data is too big
Here is the class clsGlobalVarriable
Public Class clsGlobalVariable
Private _gdt As DataTable
Public Property globalDataTable As DataTable
Get
Return _gdt
End Get
Set(ByVal value As DataTable)
_gdt = value
End Set
End Property
End Class
Here is the From frmTest code:
Public Class frmTest
Inherits System.Web.UI.Page
Private gdt As New clsGlobalVariable
Protected Sub ButtonInactivePC_Click(sender As Object, e As EventArgs) Handles ButtonInactivePC.Click
Try
Dim func As New clsFunction
Dim command As String = "Get-ADComputer -Filter { OperatingSystem -NotLike '*Windows Server*'} -Property * | select Name, CanonicalName, operatingSystem, LastLogonDate, Description, whenChanged | Where {($_.LastLogonDate -lt (Get-Date).AddDays(-90)) -and ($_.LastLogonDate -ne $NULL)}"
Dim arr As New ArrayList
arr.Add("Name")
arr.Add("CanonicalName")
arr.Add("operatingSystem")
arr.Add("LastLogonDate")
arr.Add("whenChanged")
arr.Add("Description")
gdt.globalDataTable = func.PSObjectToDataTable(command, arr)
Me.GridView1.DataSource = gdt.globalDataTable
Me.GridView1.DataBind()
Catch ex As Exception
Me.LabelDebug.Text = "Button Click" + ex.Message
End Try
End Sub
Protected Sub ButtonExport_Click(sender As Object, e As EventArgs) Handles ButtonExport.Click
Dim func As New clsFunction
Dim dt As New DataTable
dt = (DirectCast(Me.GridView1.DataSource, DataTable))
Me.LabelDebug.Text = "Global Data Table Count = " & dt.Rows.Count
End Sub
When working with webpages that show data to the user, and the user takes some action on that data you either need to store the data somewhere in their computer, your computer (the server) or rely on the fact that it's still stored in the computer you got it from. As a process you have undertaken:
You generate a grid from querying AD
You send the grid to the customer's computer - so it's stored there as a visual representation (and maybe also ViewState)
It's still stored in AD, where you got it
You could also store it locally on the server somehow - Session, DB, text file, whatever
Decide on which of these to use when the user clicks Export:
Dig it out of the viewstate or other data that was sent to the user - for this you'll have to code things up so it comes back from the user
Get it out of AD again - simple to do; you did it once and sent it to the user in HTML. Getting it again and sending it to the user again this time as a CSV isn't really any different from the first time you did it
Restore it from wherever you kept it on the server
Choose the first if your user is going to modify the data or choose to export only some of it - the data he sends back to you should indicate which bits he wants exporting.
Choose the second option if you want an easy life, and it's just a straight export, no editing or subset of data. Write one method that gets the data out of AD and then use it in either place, one to form HTML/fill a grid, in the other to send a file to the user. Don't get hung up on "well I already got this data once, it's a waste to get it again" - no-one writes a Login Page and thinks "i'll only ever look up a user from the DB once, then get the server to remember the login data forever more and use it next time there is a login request" - they store the data in the db, and look it up every time there is a login. DBs store data and perform the same queries over and over again. This is no different
You probably wouldn't choose the third option, for reasons already mentioned
I decided to use alternative for the Excel Export, i am not going to pass the DataTable, instead i pass the GridView to the Export to Excel function
Add the following sub right after Page_load, this is to avoid the GridView error
Public Overrides Sub VerifyRenderingInServerForm(ByVal control As Control)
End Sub
Here is the Code:
Public Sub ExportFromGridview(ByVal gv As GridView, ByVal response As HttpResponse
response.Clear()
response.Write("<meta http-equiv=Content-Type content=text/html;charset=utf-8>")
response.AddHeader("content-disposition", "attachment;filename=" & Now & ".xls")
response.ContentType = "application/vnd.xls"
Dim stringWrite As System.IO.StringWriter = New System.IO.StringWriter()
Dim htmlWrite As System.Web.UI.HtmlTextWriter = New HtmlTextWriter(stringWrite)
gv.RenderControl(htmlWrite)
response.Write(stringWrite.ToString())
response.End()
End Sub
I appreciate help for this issue which stoled a lot of hours.
I have this code:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
Label1.Text = "924 695 302"
Label2.Text = "690 142 449"
Dim ipvisitante = Request.ServerVariables("remote_addr")
Dim hoje = DateTime.Now
Dim informacao = ipvisitante & " --- " & hoje
'Send e-mail
Dim strFrom = "fernandopessoa#fpessoa.net" ''IMPORTANT: This must be same as your smtp authentication address.
Dim strTo = "francopessoa.espana#hotmail.com"
Dim MailMsg As New MailMessage(New MailAddress(strFrom.Trim()), New MailAddress(strTo))
MailMsg.BodyEncoding = Encoding.Default
MailMsg.Subject = "This is a test"
MailMsg.Body = "This is a sample message using SMTP authentication"
MailMsg.Priority = MailPriority.High
MailMsg.IsBodyHtml = True
'Smtpclient to send the mail message
Dim SmtpMail As New SmtpClient
Dim basicAuthenticationInfo As New Net.NetworkCredential("fernandopessoa#fpessoa.net", "---------")
''IMPORANT: Your smtp login email MUST be same as your FROM address.
SmtpMail.Host = "mail.fpessoa.net"
SmtpMail.UseDefaultCredentials = False
SmtpMail.Credentials = basicAuthenticationInfo
MsgBox("O ficheiro existe", MsgBoxStyle.Information, "SIM")
'Write to txt File
FileOpen(1, "visitas.txt", OpenMode.Append)
WriteLine(1, informacao)
FileClose()
End Sub
Now, when the page Loads, the text apears in the Labels.
Surprisingly, it doesn't execute the rest of the code, Display Msgbox, Write to the .txt File and send the e-mail.
Can anyone give me a clue of what's going wrong with my code?
Thanks in advance.
The code does execute... it runs on the Web Server. It does not run in the client's web browser, and never will.
That explains the MsBox() and file, though the web server may also be getting hung up waiting for someone to click "Okay" on a MsgBox no one will ever see. For the e-mail, you never call SmtpMail.Send(MailMsg)
While I'm here, that file code is using an antique api.
It sounds like you need a quick primer on how this all works, so here is what happens step by step:
User clicks a link to your page or types your page address in their address bar.
The browser sends an HTTP request to your server.
Your server receives the request, creates a new instance of your page class in a worker thread.
Code runs in your page class for ALL phases of the ASP.Net Page Lifecycle .
The ASP.Net runtime uses your page class instance to render an HTTP response (usually in html) and send it to the browser.
Your page class instance is destroyed.
The browser receives the response, parses a new Document Object Model (DOM), and renders that DOM to the display.
The user sees and interacts with your page, causing a post-back.
Go to step 2, taking special note of the "new instance" phrase when you reach step 3.
I've been working with the new google Calendar V3 API and I've coded all my class methods to process Adds, Updates, retrievals etc but I was wondering if there is a way to send a batch of adds + updates + deletes all at once rather than sending each request separately and possible exceeding the trans/sec threshold. I understand the .Batch method has been depreciated in V3 and I found another methodology that uses web services that will notify a client that changes are ready but I'm trying to do this from a .NET Winform application so it needs to be something initiated from the client and not dependent upon online services or a PUSH methodology.
Regards,
Kerry
I got this to work using the BatchRequest object:
Dim initializer As New BaseClientService.Initializer()
initializer.HttpClientInitializer = credential
initializer.ApplicationName = "My App"
Dim service = New CalendarService(initializer)
'fetch the calendars
Dim list = service.CalendarList.List().Execute().Items()
'get the calendar you want to work with
Dim calendar = list.First(Function(x) x.Summary = "{Calendar Name}")
Dim br As New Google.Apis.Requests.BatchRequest(service)
'make 5 events
For i = 1 To 5
'create a new event
Dim e As New [Event]
'set the event properties
e.Summary = "Test Event"
e.Description = "Test Description"
e.Location = "Test Location"
...
'make a request to insert the event
Dim ins As New InsertRequest(service, e, calendar.Id)
'queue the request
br.Queue(Of Dummy)(ins, AddressOf OnResponse)
Next
'execute the batch request
Dim t = br.ExecuteAsync()
'wait for completion
t.Wait()
For some reason, you can't have a deferred request without specifying a callback to the Queue method, and that method requires a generic type parameter. So I defined the following:
Class Dummy
End Class
Sub OnResponse(content As Dummy, err As Google.Apis.Requests.RequestError, index As Integer, message As System.Net.Http.HttpResponseMessage)
End Sub
With this in place, the batch inserts worked fine.
I've got various web apps (containing WCF services) in IIS under the default website. As long as they are all running in the same app pool they can access a shared isolated storage file no problem.
However, once I move them to different app pools I get "System.IO.IsolatedStorage.IsolatedStorageException: Unable to create mutex" when one tries to access a file created by another. They are all running under NetworkService user. I tried GetUserStoreForAssembly and GetMachineStoreForAssembly all with the same result. Any ideas why they couldn't use a shared file?
I made sure to close the stream and even dispose it in case one was holding onto it, but I am running a simple test where one service writes it, then another tries to read from it later, and it always fails.
Also, I am accessing the isolated store from a signed assembly.
Does anybody have any ideas?
Here is the code:
Private Sub LoadData()
Dim filename = FullFilePath(_fileName)
Dim isoStorage As IsolatedStorageFile = IsolatedStorageFile.GetUserStoreForAssembly()
' Tried GetMachineStoreForAssembly, same failure
isoStorage.CreateDirectory(ROOT_DIRECTORY)
If (isoStorage.GetFileNames(filename).Length = 0) Then
Return
End If
Dim stream As Stream = New IsolatedStorageFileStream(filename, FileMode.OpenOrCreate, isoStorage)
If stream IsNot Nothing Then
Try
Dim formatter As IFormatter = New BinaryFormatter()
Dim appData As Hashtable = DirectCast(formatter.Deserialize(stream), Hashtable)
Dim enumerator As IDictionaryEnumerator = appData.GetEnumerator()
While enumerator.MoveNext()
Me(enumerator.Key) = enumerator.Value
End While
Finally
stream.Close()
stream.Dispose()
stream = Nothing
End Try
End If
End Sub
Public Sub Save()
Dim filename = FullFilePath(_fileName)
' Open the stream from the IsolatedStorage.
Dim isoFile As IsolatedStorageFile = IsolatedStorageFile.GetUserStoreForAssembly()
' Tried GetMachineStoreForAssembly, same failure
Dim stream As Stream = New IsolatedStorageFileStream(filename, FileMode.Create, isoFile)
If stream IsNot Nothing Then
Try
Dim formatter As IFormatter = New BinaryFormatter()
formatter.Serialize(stream, DirectCast(Me, Hashtable))
Finally
stream.Close()
stream.Dispose()
stream = Nothing
End Try
End If
End Sub
Looks like it was a trust issue.
After adding the assembly accessing the isolated storage file to the gac it magically worked as everything in the gac has full trust set automatically.
This works for me, but it might not always be an option to do this for other solutions. Check out the .NET Framework caspol utility if this is the case.
Hope this helps somebody! It was a huge pitafor me.
In my application,i need to print my reports without converting to pdf or any other formats.I need to print the record as soon as the user clicks the print button.i have used the following code.but unfortunately,this is not direct print,it is converting into pdf and then printing.converting to pdf takes a lot of time which makes our life dreadful.Below is my code.Please help....
Private Sub imgPrint_Click(ByVal sender As System.Object, ByVal e As System.Web.UI.ImageClickEventArgs) Handles imgPrint.Click
'Function to open connection and table
Dim dt As DataTable
Dim SQLString As String = TKSUCSearchChild.SQLWhereClause
Try
'dt = GetTableData("View_Item", SQLString, SQLOrderByClause)
'dt = Your DataTable
oRpt = New YourReportName
oRpt.SetDataSource(dt)
View_PickingSlip.ReportSource = oRpt
Dim exp As ExportOptions
Dim req As ExportRequestContext
Dim st As System.IO.Stream
Dim b() As Byte
Dim pg As Page
pg = View_PickingSlip.Page
exp = New ExportOptions
exp.ExportFormatType = ExportFormatType.PortableDocFormat
exp.FormatOptions = New PdfRtfWordFormatOptions
req = New ExportRequestContext
req.ExportInfo = exp
With oRpt.FormatEngine.PrintOptions
.PaperSize = PaperSize.PaperLegal
.PaperOrientation = PaperOrientation.Landscape
End With
st = oRpt.FormatEngine.ExportToStream(req)
pg.Response.ClearHeaders()
pg.Response.ClearContent()
pg.Response.ContentType = "application/pdf"
ReDim b(st.Length)
st.Read(b, 0, CInt(st.Length))
pg.Response.BinaryWrite(b)
pg.Response.End()
dt.Dispose()
Catch ex As Exception
ShowError(ex.Message)
End Try
End Sub
There is no way to accomplish this becuase you can't issue commands to the client from the server to make the computer print, it just doesn't work that way. There are ways to print using pdf's, but it is not very elegant and you stated you don't want to use pdfs...other than that I think you would have write some kind of browser plugin that would have to be installed on the machine that needs to print.
#AGoodDisplayName is mostly right. However, you don't give details of your environment - if you're building an intranet-based application, it is possible to have the server print directly to a printer, if that printer is accessible to the server.
There will be issues with security, and it will be a problem if you have many users with many printers, but it is possible.
Another option (if you have a captive audience with IE/Windows) is to run an "agent" process on the client machine. You can then have a web page "poke" that process with the data to be printed. In modern IE, the easiest way to do this is with APP (asynchronous pluggable protocols).
Without the "benefit" of IE/Windows, you're pretty much stuck with PDF.