HTMLInputFile giving "object reference not set to instance of object" 1

[lanm]

The subroutine getting called is:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'Call Upload()
Dim FileInput As HtmlInputFile

If FileInput.PostedFile Is "" Then
Label2.Text = "No File specified"
Else
Try
Dim ServerFileName As String
ServerFileName = Path.GetFileName(FileInput.PostedFile.FileName)
FileInput.PostedFile.SaveAs("C:\TestSaving\" & ServerFileName)
Label2.Text = "File " & ServerFileName & " uploaded successfully."
Catch ex As Exception
Label2.Text = ex.Message
End Try
End If
End Sub

 

[jbenson001]

What line is the error happening on?

 

[lanm]

The error happens @:

If FileInput.PostedFile is "" Then

**************************

...I've also tried the following code:

I've got:
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

End Sub
Protected WithEvents myfile As System.Web.UI.HtmlControls.HtmlInputFile

.....the routine is:

Dim getfile As HtmlInputFile
If IsNothing(getfile.PostedFile) Then Label2.Text = "please select a file to opload" : Exit Sub
If getfile.PostedFile.ContentLength = 0 Then Label2.Text = "cannot upload zero length file" : Exit Sub
Dim myFile As HttpPostedFile = getfile.PostedFile
'myFile.SaveAs(Server.MapPath("." & "\upload\template.xls"))
Dim ServerFileName As String = Path.GetFileName(getfile.PostedFile.FileName)
myFile.SaveAs("C:\TestSaving\" & ServerFileName)

I get the object reference error on the line for:
"If IsNothing(getfile.PostedFile) Then Label2.Text = "please select a file to opload......"

 

[jbenson001]

Try : Dim FileInput As New HtmlInputFile

 

[lanm]

K...just did:
Dim FileInput As New HtmlInputFile
If FileInput.PostedFile Is "" Then
Label2.Text = "No File specified"
Else
Try
Dim ServerFileName As String
ServerFileName = Path.GetFileName(FileInput.PostedFile.FileName)
FileInput.PostedFile.SaveAs("C:\TestSaving\" & ServerFileName)
Label2.Text = "File " & ServerFileName & " uploaded successfully."
Catch ex As Exception
Label2.Text = ex.Message
End Try
End If


...and this time, I got the label2.Text to show me the message of "Object reference not set to an instance of an object." Before, it was basically the "Run Time" page error.

 

[jbenson001]

Try using this

If Not (FileInput.PostedFile Is Nothing) Then
..
End IF

 

[lanm]

Hmmmm....just did:
Dim FileInput As New HtmlInputFile
If Not (FileInput.PostedFile Is Nothing) Then
Try
Dim ServerFileName As String
ServerFileName = Path.GetFileName(FileInput.PostedFile.FileName)
FileInput.PostedFile.SaveAs("C:\TestSaving\" & ServerFileName)
Label2.Text = "File " & ServerFileName & " uploaded successfully."
Catch ex As Exception
Label2.Text = ex.Message
End Try
Else
Label2.Text = "No File specified"
End If

..and got "No File Specified" even though I selected a .doc file for testing.

 

[lanm]

Finally got this to work:

Dim getmyFile As HttpPostedFile = myfile.PostedFile
Label2.Text = "Line 76"
If IsNothing(getmyFile) Then
Label2.Text = "Please select a file to upload"
Label2.Text = "Line 78"
Else
If getmyFile.ContentLength = 0 Then
Label2.Text = "Cannot upload zero length File"
Else
Dim ServerFileName As String = Path.GetFileName(myfile.PostedFile.FileName)
getmyFile.SaveAs("C:\TestSaving\" & ServerFileName)
Label2.Text = "Successful upload to C:\TestSaving\" & ServerFileName
End If
End If

 

[vbkris]

if u r referring to a control in code behind then have to delcare it likeso:
protected WithEvents ControlName as ControlType

so this would work:
Protected WithEvents myFile As HttpPostedFile

Known is handfull, Unknown is worldfull

 

[lanm]

I have:

Protected WithEvents myfile as System.Web.UI.HTMLControls.HTMLInputFile

Thanks!

 

[vbkris]

it works???

Known is handfull, Unknown is worldfull

 

[lanm]

Yes, I was finally able to get it to go this morning after working on it all day yesterday.

 

[vbkris]

cheers ...

Known is handfull, Unknown is worldfull

 

[ca8msm]

Just as a bit of a side note, rather that just check if the posted file is nothing, I would suggest a few more checks such as the minumum and maximum file size. e.g.

    Public Function FileFieldSelected(ByVal FileField As System.Web.UI.HtmlControls.HtmlInputFile) As Boolean
        If FileField.PostedFile Is Nothing Then Return False
        If FileField.PostedFile.ContentLength = 0 Then Return False
        If FileField.PostedFile.ContentLength > 5120000 Then Return False
        Return True
    End Function

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[abduk]

The reason why u get that error is because you need to set the HTML File Input control to "run as server control";

if you r using vs .net right click and check and check "run as server control".