[RESOLVED] Buffer cannot be null

I'm trying to get values from DataGridView to the another form in textboxes and in Picturebox ,data in textboxes are there but when I trying to get a picture in a picturebox from DB it gives me this error

Attachment 95507

and here is the code

Code:

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Private Sub dgv1_CellDoubleClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DGV1.CellDoubleClick
        Dim frm As New Edit_Employee()
        frm.MdiParent = Mainfrm
        frm.Show()
       
        frm.TextBox1.Text = DGV1.Rows(e.RowIndex).Cells(1).Value.ToString
        frm.TextBox2.Text = DGV1.CurrentRow.Cells(2).Value.ToString
        frm.TextBox3.Text = DGV1.CurrentRow.Cells(3).Value.ToString
        frm.TextBox4.Text = DGV1.CurrentRow.Cells(4).Value.ToString
        frm.TextBox5.Text = DGV1.CurrentRow.Cells(5).Value.ToString
        frm.TextBox6.Text = DGV1.CurrentRow.Cells(6).Value.ToString
        frm.TextBox7.Text = DGV1.CurrentRow.Cells(7).Value.ToString
        frm.TextBox8.Text = DGV1.CurrentRow.Cells(8).Value.ToString
        frm.DateTimePicker1.Text = DGV1.CurrentRow.Cells(9).Value.ToString
        frm.TextBox9.Text = DGV1.CurrentRow.Cells(10).Value.ToString
        frm.TextBox10.Text = DGV1.CurrentRow.Cells(11).Value.ToString
        frm.TextBox11.Text = DGV1.CurrentRow.Cells(12).Value.ToString
        frm.TextBox12.Text = DGV1.CurrentRow.Cells(13).Value.ToString
        frm.TextBox13.Text = DGV1.CurrentRow.Cells(14).Value.ToString
        frm.TextBox14.Text = DGV1.CurrentRow.Cells(15).Value.ToString
        frm.TextBox15.Text = DGV1.CurrentRow.Cells(16).Value.ToString
        frm.DateTimePicker2.Text = DGV1.CurrentRow.Cells(17).Value.ToString
        frm.DateTimePicker3.Text = DGV1.CurrentRow.Cells(18).Value.ToString
        frm.TextBox16.Text = DGV1.CurrentRow.Cells(19).Value.ToString
        frm.TextBox17.Text = DGV1.CurrentRow.Cells(20).Value.ToString
        frm.TextBox18.Text = DGV1.CurrentRow.Cells(21).Value.ToString
        frm.TextBox19.Text = DGV1.CurrentRow.Cells(22).Value.ToString
        frm.Txtbonus.Text = DGV1.CurrentRow.Cells(23).Value.ToString
        frm.TextBox21.Text = DGV1.CurrentRow.Cells(24).Value.ToString
       

        Try
            Dim connection As New SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Users\Danial\documents\visual studio 2010\Projects\ESI_PF_Payroll_V1\ESI_PF_Payroll_V1\Pay.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True")
            Dim command As New SqlCommand("SELECT Imagedata FROM Employee WHERE Firstname = '" & TextBox1.Text & "'", connection)

            connection.Open()

            Dim pictureData As Byte() = DirectCast(command.ExecuteScalar(), Byte())

            connection.Close()

            Dim picture As Image = Nothing

            'Create a stream in memory containing the bytes that comprise the image.
            Using stream As New IO.MemoryStream(pictureData)
                'Read the stream and create an Image object from the data.
                picture = Image.FromStream(stream)
               
                frm.PB1.Image = (picture)
            End Using
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try

       
        frm.Txtfilepath1.Text = DGV1.CurrentRow.Cells(27).Value.ToString
        frm.Txtfilename.Text = DGV1.CurrentRow.Cells(26).Value.ToString
        frm.TxtGross.Text = DGV1.CurrentRow.Cells(28).Value.ToString
        frm.RTB1.Text = DGV1.CurrentRow.Cells(29).Value.ToString
    End Sub

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It would be nice if you temporarily removed your Try Catch code so that you could tell us which line you're getting the error. But I suspect that you get it on your Using stream line and that your pictureData is null.

Clearly pictureData is null causing the failure of the Stream.

Quote:

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Originally Posted by Joacim Andersson

It would be nice if you temporarily removed your Try Catch code so that you could tell us which line you're getting the error. But I suspect that you get it on your Using stream line and that your pictureData is null.

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Yes you are right I'm getting an error on that line.
here is the screen shot without Try and catch

Attachment 95531
How can I change the code to make it work?

Yes, so obviously your query does not return a byte array.

ok my sql query has a problem ?

Yes, obviously this call returns null.

Code:

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Dim pictureData As Byte() = DirectCast(command.ExecuteScalar(), Byte())

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Try setting a break point at this line as see what you get.

I have changed the Sql statement ..where clause is gone,I have got the image but not according to the name,just one picture is showing no matter which row I click .

Code:

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Dim connection As New SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Users\Danial\documents\visual studio 2010\Projects\ESI_PF_Payroll_V1\ESI_PF_Payroll_V1\Pay.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True")
        connection.Open()
        Dim command As New SqlCommand("SELECT Imagedata FROM Employee ", connection)
Dim pictureData As Byte() = DirectCast(command.ExecuteScalar(), Byte())
        connection.Close()
        Dim picture As Image = Nothing

        'Create a stream in memory containing the bytes that comprise the image.
        Using stream As New IO.MemoryStream(pictureData)
            'Read the stream and create an Image object from the data.
            picture = Image.FromStream(stream)
            frm.PB1.Image = (picture)
        End Using

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Yes, you're calling ExecuteScalar which will only return 1 result. Call ExecuteReader instead and loop through the result.

My where clause has the problem ...so I changed it to this

Code:

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where Firstname = '" & _
                  DGV1.CurrentRow.Cells(1).Value() & "'"

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and now it works fine :)
Thank you all for guiding me and helping me in this thread ,I have learned some new things in this process .I hope I will keep that in mind.

Now how do I make this thread [solved]?

Pull down the Thread Tools menu close to the top and select Mark as resolved.