'Where the program save the file Delegate Sub ChangeTextsSafe ( ByVal length As Long , ByVal position As Integer , ByVal percent As Integer , ByVal speed As Double ) Delegate Sub DownloadCompleteSafe ( ByVal cancelled As Boolean ) Public Sub DownloadComplete ( ByVal cancelled As Boolean ) Me . txtFileName . Enabled = True Me . btnDownload . Enabled = True Me . btnCancel . Enabled = False If cancelled Then Me . Label4 . Text = "Cancelled" 'MessageBox.Show("Download aborted", "Aborted", MessageBoxButtons.OK, MessageBoxIcon.Information) Else Me . Label4 . Text = "Successfully downloaded" 'MessageBox.Show("Successfully downloaded!", "All OK", MessageBoxButtons.OK, MessageBoxIcon.Information) End If Me . ProgressBar1 . Value = 0 Me . Label5 . Text = "Downloading: " Me . Label6 . Text = "Save to: " Me . Label3 . Text = "File size: " Me . Label2 . Text = "Download speed: " Me . Label4 . Text = "" End Sub Public Sub ChangeTexts ( ByVal length As Long , ByVal position As Integer , ByVal percent As Integer , ByVal speed As Double ) Me . Label3 . Text = "File size: " & Math. Round ( ( length / 1024 ) , 2 ) & " KB" Me . Label5 . Text = "Downloading: " & Me . txtFileName . Text Me . Label4 . Text = "Downloaded " & Math. Round ( ( position / 1024 ) , 2 ) & " KB of " & Math. Round ( ( length / 1024 ) , 2 ) & "KB (" & Me . ProgressBar1 . Value & "%)" If speed = - 1 Then Me . Label2 . Text = "Download speed: calculating..." Else Me . Label2 . Text = "Download speed: " & Math. Round ( ( speed / 1024 ) , 2 ) & " KB/s" End If Me . ProgressBar1 . Value = percent End Sub Private Sub btnDownload_Click ( ByVal sender As System. Object , ByVal e As System. EventArgs ) Handles btnDownload. Click If Me . txtFileName . Text <> "" AndAlso Me . txtFileName . Text . StartsWith ( "http://" ) Then Me . SaveFileDialog1 . FileName = Me . txtFileName . Text . Split ( "/" c ) ( Me . txtFileName . Text . Split ( "/" c ) . Length - 1 ) If Me . SaveFileDialog1 . ShowDialog = Windows. Forms . DialogResult . OK Then Me . whereToSave = Me . SaveFileDialog1 . FileName Me . SaveFileDialog1 . FileName = "" Me . Label6 . Text = "Save to: " & Me . whereToSave Me . txtFileName . Enabled = False Me . btnDownload . Enabled = False Me . btnCancel . Enabled = True Me . BackgroundWorker1 . RunWorkerAsync ( ) 'Start download End If Else MessageBox. Show ( "Please insert valid URL for download" , "Warning" , MessageBoxButtons. OK , MessageBoxIcon. Warning ) End If End Sub Private Sub btnCancel_Click ( ByVal sender As System. Object , ByVal e As System. EventArgs ) Handles btnCancel. Click Me . BackgroundWorker1 . CancelAsync ( ) 'Send cancel request Try Me . bckZip . CancelAsync ( ) Catch ex As Exception 'Do Nothing End Try End Sub Private Sub BackgroundWorker1_DoWork ( ByVal sender As System. Object , ByVal e As System. ComponentModel . DoWorkEventArgs ) Handles BackgroundWorker1. DoWork 'Creating the request and getting the response Dim theResponse As HttpWebResponse Dim theRequest As HttpWebRequest Try 'Checks if the file exist theRequest = WebRequest. Create ( Me . txtFileName . Text ) theResponse = theRequest. GetResponse theRequest. Timeout = 10000000 Catch ex As Exception MessageBox. Show ( "An error occurred while downloading file. Possibe causes:" & ControlChars. CrLf & _ "1) File doesn't exist" & ControlChars. CrLf & _ "2) Remote server error" , "Error" , MessageBoxButtons. OK , MessageBoxIcon. Error ) Dim cancelDelegate As New DownloadCompleteSafe ( AddressOf DownloadComplete ) Me . Invoke ( cancelDelegate, True ) Exit Sub End Try Dim length As Long = theResponse. ContentLength 'Size of the response (in bytes) Dim safedelegate As New ChangeTextsSafe ( AddressOf ChangeTexts ) Me . Invoke ( safedelegate, length, 0 , 0 , 0 ) 'Invoke the TreadsafeDelegate Dim writeStream As New IO. FileStream ( Me . whereToSave , IO. FileMode . Create ) 'Replacement for Stream.Position (webResponse stream doesn't support seek) Dim nRead As Integer 'To calculate the download speed Dim speedtimer As New Stopwatch Dim currentspeed As Double = - 1 Dim readings As Integer = 0 Do If BackgroundWorker1. CancellationPending Then 'If user abort download Exit Do End If speedtimer. Start ( ) Dim readBytes ( 4096 ) As Byte Dim bytesread As Integer = theResponse. GetResponseStream . Read ( readBytes, 0 , 4096 ) nRead += bytesread Dim percent As Integer = ( nRead / length ) * 100 Me . Invoke ( safedelegate, length, nRead, percent, currentspeed ) If bytesread = 0 Then Exit Do writeStream. Write ( readBytes, 0 , bytesread ) speedtimer. Stop ( ) readings += 1 If readings > = 5 Then 'For increase precision, the speed it's calculated only every five cicles currentspeed = 20480 / ( speedtimer. ElapsedMilliseconds / 1000 ) speedtimer. Reset ( ) readings = 0 End If Loop 'Close the streams theResponse. GetResponseStream . Close ( ) writeStream. Close ( ) If Me . BackgroundWorker1 . CancellationPending Then IO. File . Delete ( Me . whereToSave ) Dim cancelDelegate As New DownloadCompleteSafe ( AddressOf DownloadComplete ) Me . Invoke ( cancelDelegate, True ) Exit Sub End If Dim completeDelegate As New DownloadCompleteSafe ( AddressOf DownloadComplete ) Me . Invoke ( completeDelegate, False ) End Sub Dim whereToSave Kot String "Če program shranite delegat Sub ChangeTextsSafe (ByVal dolžina tako dolgo, položaj ByVal Kot Integer, ByVal odstotkov Kot Integer, ByVal hitrost Kot Double) Delegat Sub DownloadCompleteSafe (ByVal odpovedan Kot Boolean) Javno Sub DownloadComplete (ByVal odpovedan Kot Boolean) Me. txtFileName =. Omogočeno True Me. btnDownload. Enabled = True Me. btnCancel. Enabled = False Če odpovedan Potem me. Label4. Besedilo = "Preklicano" "MessageBox.Show (" Download splavile "," prekinjena ", MessageBoxButtons.OK, MessageBoxIcon.Information) Else Me. Label4 =. Besedilo, ki ga "uspešno prenesli" "MessageBox.Show (" uspešno prenesli! "," All OK ", MessageBoxButtons.OK, MessageBoxIcon.Information) Konec Če Me. ProgressBar1. Value = 0 Me. Label5 =. Besedilo "Prenos:" Me. Label6 ". Besedilo = Shrani v:" Me. Label3. Besedilo = "File size:" Me. Label2. Besedilo = "Download hitrost:" Me. Label4. Besedilo = "" End Sub Sub javno ChangeTexts (ByVal dolžina tako dolgo, položaj ByVal Kot Integer, ByVal odstotkov Kot Integer, ByVal hitrost Kot Double) Me. Label3 =. Besedilo "File size:" & Math (. kroga (dolžina / 1024) , 2) & "KB" Me. Label5 =. Besedilo "Prenos:" Me &. txtFileName. Besedilo Me. Label4. Besedilo = "Downloaded" & Math (. krog (mesto / 1024), 2) & "KB" in Math (. kroga (dolžina / 1024), 2) & "KB (" & Me. ProgressBar1 &. Value "%):" Če hitrost = - 1 potem mi. Label2. Besedilo = "Download hitrost: izračun ..." Else Me. Label2 =. besedilo "Download hitrost:" & Math (. krog (hitrost / 1024), 2) & "KB / s" End Če Me. ProgressBar1. Value = odstotkih End Sub Private Sub btnDownload_Click (ByVal pošiljatelj kot sistemski . Object, ByVal e kot sistem. EventArgs) Ročaji btnDownload. Kliknite Če Me. txtFileName. Besedilo <> "" AndAlso Me. txtFileName. besedila. StartsWith ("http://"), mi potem. SaveFileDialog1. FileName = Me. txtFileName . besedila ". Split (/" c) (Me. txtFileName. besedila. Split ("/" c) -. Dolžina 1) Če Me. SaveFileDialog1. ShowDialog = Windows. Forms. DialogResult. OK potem mi. whereToSave Me =. SaveFileDialog1. FileName Me. SaveFileDialog1. FileName = "" Me. Label6 ". Besedilo = Shrani v:" & Me. Me whereToSave. txtFileName. Enabled = False Me. btnDownload. Enabled = False Me. btnCancel. Enabled = True Me. BackgroundWorker1 . RunWorkerAsync () "Start download End Če Else vest". Show ("Please insert veljaven URL za download," Opozorilo ", MessageBoxButtons. OK, MessageBoxIcon. Opozorilo) End Če End Sub Private Sub btnCancel_Click (ByVal pošiljatelj kot sistem. Object, ByVal e kot sistem. EventArgs) Ročaji btnCancel Me. Kliknite. BackgroundWorker1 ". CancelAsync () Send Zahtevo za preklic Me Try. bckZip. CancelAsync () Catch ex Kot izjema" Ali nič End Try End Sub Private Sub BackgroundWorker1_DoWork (ByVal pošiljatelj kot sistem. Objekt, ByVal e kot sistem DoWorkEventArgs. ComponentModel.) Ročaji BackgroundWorker1. DoWork "Ustvarjanje zahtevo in pridobivanje Dim theResponse odziv, saj Dim theRequest HttpWebResponse Kot HttpWebRequest Poskusite 'Preveri, če datoteka obstaja theRequest = WebRequest. Ustvari (Me. txtFileName. Besedilo) theResponse = theRequest theRequest. GetResponse. Timeout = 10000000 Catch ex Kot Izjema vest napake. Show ("prišlo med nalaganjem datoteke vzrokov. Possibe:" & ControlChars. CRLF & _ "1) Datoteka ne obstaja" & ControlChars. CRLF & _ "2) Remote napake na strežniku", "Error", MessageBoxButtons. OK, MessageBoxIcon. Error) Dim cancelDelegate Kot New DownloadCompleteSafe (AddressOf DownloadComplete) Me. Prikliči (cancelDelegate, True) Exit Sub End Try Dim dolžine, dokler = theResponse. ContentLength "Velikost odziva (v bajtih) Dim safedelegate Kot New ChangeTextsSafe (AddressOf ChangeTexts) Me. Prikliči (safedelegate, dolžina, 0, 0, 0)" Prikliči TreadsafeDelegate Dim writeStream Kot New IO (. FileStream Me. whereToSave, IO. . "Ustvari) zamenjava FileMode za Stream.Position (webResponse stream ne podpira iščejo) Dim nRead Kot Integer" Za izračun download Dim speedtimer hitrost Kot New Štoparica Dim currentspeed Kot Double = - 1 odčitki Dim Kot Integer = 0 storiti, če BackgroundWorker1 . CancellationPending Nato "Če uporabnik prekine download Exit Ali Konec Če speedtimer. Start () Dim readBytes (4096) Kot Byte Dim bytesread Kot Integer = theResponse. GetResponseStream. Read (readBytes, 0, 4096) nRead + = bytesread Dim odstotkov Kot Integer = (nRead / dolžina) * 100 Me. Prikliči (safedelegate, dolžina, nRead, odstotkov, currentspeed) Če bytesread = 0 Potem Izhod Ali writeStream. Write (readBytes, 0, bytesread) speedtimer. Stop () branja + = 1 Če branja> = 5 Nato "Za povečanje natančnosti, hitrosti, je bilo izračunano le vsakih pet cicles currentspeed = 20480 / (speedtimer. ElapsedMilliseconds / 1000) speedtimer. Reset () branja = 0 End Če Loop" Zapri tokov theResponse. GetResponseStream. Close () writeStream . Close () Če Me. BackgroundWorker1. CancellationPending Potem IO. File (. Delete Me. whereToSave) Dim cancelDelegate Kot New DownloadCompleteSafe (AddressOf DownloadComplete) Me. Prikliči (cancelDelegate, True) Exit Sub End Če Dim completeDelegate Kot New DownloadCompleteSafe (AddressOf DownloadComplete Me) Sub. Prikliči (completeDelegate, False) End