If (fileUpload.HasFile)=false

Question

hi all here the code then i will explain my question:-

 Protected Sub btnupload_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnUpload.Click
    If (IsPostBack) Then
        HandleUploadedFile()
        Dim savePath As String = "Images\"
        If (fileUpload.HasFile) Then
            Dim fileName As String = fileUpload.FileName
            savePath = Server.MapPath(savePath) + fileName
            fileUpload.SaveAs(savePath)
            Me.Label1.Text = "Your file was saved as " & fileName
            adp.Insert(fileUpload.FileName)
        Else
            Me.Label1.Text = "You did not specify a file to upload."
        End If
    End If
End Sub

every time i track the code it says that (fileUpload.HasFile)=false and never sees the code after that, then jumps to the else statment and thats the rest of the code

Private Sub HandleUploadedFile()
    ' get the root of the web site 
    Dim root As String = Server.MapPath("~/")

    ' clean up the path 
    If Not root.EndsWith("\") Then
        root += "\"
    End If

    ' make a folder to store the images in 
    Dim fileDirectory As String = root & "Images/"

    ' create the folder if it does not exist 
    If Not System.IO.Directory.Exists(fileDirectory) Then
        System.IO.Directory.CreateDirectory(fileDirectory)
    End If

    ' make a link to the new file 
    Dim link As String = "<a href='Images/{0}' target='_blank'>{1}</a>{2}{3}"

    ' loop through the file in the request 
    For i As Integer = 0 To Request.Files.Count - 1

        ' get the file instance 
        Dim fi As HttpPostedFile = Request.Files.[Get](i)

        ' create a byte array to store the file bytes 
        Dim fileBytes As Byte() = New Byte(fi.ContentLength - 1) {}

        ' fill the byte array 
        Using stream As System.IO.Stream = fi.InputStream
            stream.Read(fileBytes, 0, fi.ContentLength)
        End Using

        ' create a random file name 
        Dim fileName As String = Guid.NewGuid().ToString()

        'write the original file to the file system 
        File.WriteAllBytes(fileDirectory + fileName & ".jpg", fileBytes)
        litText.Text += String.Format(link, fileName & ".jpg", fileName & " Original", "<br/>", "")

        ' write the resized file to the file system 
        File.WriteAllBytes(fileDirectory + fileName & "_small.jpg", ResizeImageFile(fileBytes, 100))
        litText.Text += String.Format(link, fileName & "_small.jpg", fileName & " Small", "<br/>", "<br/>")

        ' cleanup 
        litText.Visible = True
        fileBytes = Nothing
    Next
End Sub
Private Shared Function ResizeImageFile(ByVal imageFile As Byte(), ByVal targetSize As Integer) As Byte()
    Using oldImage As System.Drawing.Image = System.Drawing.Image.FromStream(New MemoryStream(imageFile))
        Dim newSize As Size = CalculateDimensions(oldImage.Size, targetSize)
        Using newImage As New Bitmap(newSize.Width, newSize.Height, PixelFormat.Format24bppRgb)
            Using canvas As Graphics = Graphics.FromImage(newImage)
                canvas.SmoothingMode = SmoothingMode.AntiAlias
                canvas.InterpolationMode = InterpolationMode.HighQualityBicubic
                canvas.PixelOffsetMode = PixelOffsetMode.HighQuality
                canvas.DrawImage(oldImage, New Rectangle(New Point(0, 0), newSize))
                Dim m As New MemoryStream()
                newImage.Save(m, ImageFormat.Jpeg)
                Return m.GetBuffer()
            End Using
        End Using
    End Using
End Function
Private Shared Function CalculateDimensions(ByVal oldSize As Size, ByVal targetSize As Integer) As Size
    Dim newSize As New Size()
    If oldSize.Height > oldSize.Width Then
        newSize.Width = CInt((oldSize.Width * (CSng(targetSize) / CSng(oldSize.Height))))
        newSize.Height = targetSize
    Else
        newSize.Width = targetSize
        newSize.Height = CInt((oldSize.Height * (CSng(targetSize) / CSng(oldSize.Width))))
    End If
    Return newSize
End Function

End Class

Answer 1

I think it might be that you write you file to the directory and in doing that it clears out the fileupload form. This is happening before you run your if statement. Try moving your if/else above the "handleuploadedfile()" function. This should ensure that you can check the upload form before the system writes the file and removes it from the upload form.

Answer 2

The reason why fileUpload.HasFiles = False is that by the time that code is reached, the file stream has been closed inside of the HandleUploadFile Subroutine.

'this using statement closes the original input stream and there removes it 'from the FileUpload

Using stream As System.IO.Stream = fi.InputStream            
 stream.Read(fileBytes, 0, fi.ContentLength)        
End Using

Answer 3

Check if you'r using a UpdatePanel, if so then in Page.Init do something like this:

protected void userView_Init(object sender, EventArgs e)
{
 ScriptManager.GetCurrent(this).RegisterPostBackControl(uploadFileButton);
}