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How to delay the vb.net program until the file operation is completed?

I have it:

    Dim myTemp As String
    myTemp = System.DateTime.Now().ToString("MMMddyyyy_HHmmss") & ".pdf"

    System.IO.File.Copy(myFile, "c:\" & myTemp)
    Application.DoEvents()
    OpenFile(myTemp)

The problem is that when I call OpenFile, which is just a call to the helper part that opens the file, it cannot find the file. This is due to the fact that it causes it so quickly that the program does not have time to actually create the file before it is opened.

I thought DoEvents () would fix this, but it is not. I need to wait until the file is created before I open the file. How can i do this?

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11 answers

VB.NET, ? , ( )?

? OpenFile .

Dim myTemp As String
myTemp = System.DateTime.Now().ToString("MMMddyyyy_HHmmss") & ".pdf"

System.IO.File.Copy(myFile, "c:\\" & myTemp)
OpenFile("c:\\" & myTemp)
+3

, , , Invoke.

+1

,

 Function WaitForFile(fullPath, wdelay)
    Dim vd_start As Date
    vd_start = Now()
    Dim vd_end As Date
    Dim wsec, wmin, whour, wt5string As Integer
    Dim wtstring As String
    Dim count As Integer
    Dim wscale As Integer
    Dim vd_1 As Date
    Dim Vo_fileinfo As FileInfo

    Dim fs As FileStream

    wsec = Format(wdelay Mod 60, "00")
    wmin = Format(Int(wdelay / 60), "00")
    whour = Format(Int(wdelay / (60 * 60)), "00")
    wtstring = CStr(whour) + ":" + CStr(wmin) + ":" + CStr(wsec)
    Dim duration = New System.TimeSpan(0, whour, wmin, wsec)
    vd_end = vd_start.Add(duration)

    On Error GoTo error1
    Dim vsize1, vsize2 As Long
    While vd_start < vd_end
        fs = New FileStream(fullPath, FileMode.Open)
        fs.ReadByte()
        fs.Seek(0, SeekOrigin.Begin)
        fs.Close()
        Vo_fileinfo = New FileInfo(fullPath)
        vsize1 = Vo_fileinfo.Length
        Threading.Thread.Sleep(500)
        Vo_fileinfo = New FileInfo(fullPath)
        vsize2 = Vo_fileinfo.Length
        If vsize1 <> vsize2 Then GoTo error1
        GoTo finalgoto
error1:
        Err.Clear()
        vd_start = Now()
    End While

    WaitForFile = False
    GoTo Endgoto
finalgoto: WaitForFile = True
Endgoto:
End Function
+1

, .

Do Until (System.IO.File.Exists("C:\" & myTemp))
    Threading.Thread.Sleep(1)
Loop
0

, Doevents. , ( ). , , , .

:

SyncLock Me
  System.IO.File.Copy(myFile, "c:\" & myTemp)
  Application.DoEvents()
End SyncLock

OpenFile(myTemp)
0

, Application.DoEvents() , ?

0

-, DoEvents . , , , , .

Copy . OpenFile Copy.

OpenFile , , , - , - .

0

I thinf Synclock

, MSDN

SyncLock , . SyncLock, , , . , .

, - , , .

?

0
dim SourceFile as string
dim DestinationFile as string

SourceFile = "c:/archivo.txt"
DestinationFile = "c:/destino/archivo.txt"

If System.IO.File.Exists(SourceFile) = True Then

    System.IO.File.Copy(SourceFile, DestinationFile, True)
    'or
    'My.Computer.FileSystem.CopyFile(SourceFile, DestinationFile, FileIO.UIOption.AllDialogs, FileIO.UICancelOption.DoNothing)

    SourceFile = ""
    DestinationFile = ""

else

    MessageBox.Show("the file don't copy!") 

end if
0

System.Threading.Thread.Sleep(1000);

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