categories.vb

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Option Explicit On
Option Strict On
Imports System.IO

Public Class Categories

    Private blnLoaded As Boolean

    Private Sub Form_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'TODO: Delete this line of code to remove the default AutoFill for 'NorthwindDataSet.Categories'.
        Me.CategoriesTableAdapter.Fill(Me.NorthwindDataSet.Categories)
        Application.DoEvents()
        blnLoaded = True
        btnReset.Enabled = True
    End Sub

    Private Sub rbNormal_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles rbNormal.CheckedChanged
        If blnLoaded And rbNormal.Checked Then
            With CategoriesDataGridView
                Dim colImage As DataGridViewImageColumn = CType(.Columns(3), DataGridViewImageColumn)
                colImage.ImageLayout = DataGridViewImageCellLayout.Normal
            End With
        End If
    End Sub

    Private Sub rbStretch_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles rbStretch.CheckedChanged
        If blnLoaded And rbStretch.Checked Then
            With CategoriesDataGridView
                Dim colImage As DataGridViewImageColumn = CType(.Columns(3), DataGridViewImageColumn)
                colImage.ImageLayout = DataGridViewImageCellLayout.Stretch
            End With
        End If
    End Sub

    Private Sub rbZoom_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles rbZoom.CheckedChanged
        If blnLoaded And rbZoom.Checked Then
            With CategoriesDataGridView
                Dim colImage As DataGridViewImageColumn = CType(.Columns(3), DataGridViewImageColumn)
                colImage.ImageLayout = DataGridViewImageCellLayout.Zoom
            End With
        End If
    End Sub

    Private Sub btnReset_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnReset.Click
        With CategoriesDataGridView
            .Columns(3).Width = 100
            For Each rowGrid As DataGridViewRow In .Rows
                rowGrid.Height = 75
            Next
        End With
    End Sub

    Private Sub btnTestSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnTestSave.Click
        SaveBmpFile()
    End Sub

    Private Sub SaveBmpFile()
        'Save the selected file
        Dim strFile As String = Nothing
        Try
            With CategoriesDataGridView
                If .CurrentCell.ColumnIndex = 3 Then
                    If Not frmPictureBox Is Nothing Then
                        frmPictureBox.Close()
                    End If
                    Dim strType As String = .CurrentCell.ValueType.ToString
                    'Create a Byte array from the value
                    Dim bytImage() As Byte = CType(.CurrentCell.Value, Byte())
                    'Specify the image file name
                    Dim intRow As Integer = .CurrentCell.RowIndex
                    strFile = .Rows(intRow).Cells(1).Value.ToString + ".bmp"
                    'Save the image as a GIF file
                    Dim fsImage As New FileStream(Application.StartupPath + "\" + strFile, FileMode.Create)
                    fsImage.Write(bytImage, 0, bytImage.Length)
                    fsImage.Close()
                    'Create a MemoryStream and assign it as the image of a PictureBox
                    Dim msImage As New MemoryStream(bytImage)
                    frmPictureBox.pbBitmap.Image = Image.FromStream(msImage)

                    If frmPictureBox.ShowDialog = Windows.Forms.DialogResult.Yes Then
                        'Replace the CurrentCell's image from the saved version, if possible
                        If File.Exists("..\" + strFile) Then
                            'The easy was to obtain a Byte array
                            Dim bytReplace() As Byte = File.ReadAllBytes(Application.StartupPath + "\" + strFile)
                            .CurrentCell.Value = bytReplace
                            If NorthwindDataSet.HasChanges Then
                                NorthwindDataSet.AcceptChanges()
                                Dim strMsg As String = "File '" + strFile + _
                                " has replaced the image in row " + intRow.ToString + _
                                " cell 2 (" + Format(bytReplace.Length, "#,##0") + " bytes). " + _
                                vbCrLf + vbCrLf + "AcceptChanges has been applied to the DataSet."
                                MsgBox(strMsg, MsgBoxStyle.Information, "Image Replaced from File")
                            Else
                                Dim strMsg As String = "Unable to replace image with file '" + _
                                strFile + "'. DataSet does not have changes."
                                MsgBox(strMsg, MsgBoxStyle.Exclamation, "Image Not Replaced")
                            End If
                        End If
                    End If
                Else
                    MsgBox("Please select the image to save.", MsgBoxStyle.Exclamation, _
                    "No Image Selected")
                End If
            End With
        Catch exc As Exception
            With CategoriesDataGridView
                If strFile = Nothing Then
                    Dim intRow As Integer = .CurrentCell.RowIndex
                    strFile = .Rows(intRow).Cells(1).Value.ToString
                End If
            End With
            Dim strExc As String = "File '" + strFile + "' threw the following " + _
            "exception: " + exc.Message
            MsgBox(strExc, MsgBoxStyle.Exclamation, "Exception with Image")
        End Try
    End Sub

End Class