vb.net - 字节转换回图像

Question

我正在尝试将 plr.PlayerImage 中的字节转换回图片框的图像。

但是，方法1在plr.PlayerImage上返回错误“Byte类型的值无法转换为Byte的一维数组”。

方法 2 提供错误消息“从类型 Byte() 到类型 Byte 的转换无效”。

方法 1 在我从数据库中检索数据的单独子中使用时有效，但在我的新子中不起作用:

Dim pictureData As Byte() = DirectCast(drResult("PlayerImage"), Byte())

                            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)
                            End Using

                            UC_Menu_Scout1.PictureBox1.Image = picture

当前代码:

Private Sub fillPlayerInfo()

            For Each plr As Player In getAllPlayers()

                If lbPlayers.SelectedItem.PlayerID = plr.PlayerID Then

                    txtFirstName.Text = plr.PlayerFirstName
                    txtSurname.Text = plr.PlayerLastName
                    txtPlaceOfBirth.Text = plr.PlaceOfBirth
                    cmbClub.SelectedValue = plr.ClubID
                    dtpDOB.Value = plr.DOB

                    '**********Method 1*********************************************
                    Dim pictureData As Byte() = DirectCast(plr.PlayerImage, Byte())
                    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)
                    End Using

                    '**********Method 2*********************************************
                    Dim ms As New IO.MemoryStream(plr.PlayerImage)
                    Dim returnImage As Image = Image.FromStream(ms)

                    pcbEditPlayer.Image = returnImage

                End If
            Next

        End Sub

Answer 1

正如我在上面的评论中所说，您没有将您的属性转换到您创建的内存流中。此外，如果 plr.PlayerImage 未定义为 Byte()，您将得到一个异常。

它可能看起来像这样......

 Public Property PlayerImage As Byte()

这是您目前拥有的...

  Dim ms As New IO.MemoryStream(plr.PlayerImage) 'This is wrong...
  Dim returnImage As Image = Image.FromStream(ms)
  pcbEditPlayer.Image = returnImage

应该是这样...

 Dim ms As New IO.MemoryStream(CType(plr.PlayerImage, Byte())) 'This is correct...
 Dim returnImage As Image = Image.FromStream(ms)
 pcbEditPlayer.Image = returnImage