Software Expressions

   1:  Imports System.Drawing

   2:  Imports System.Runtime.Serialization

   3:  Imports System.Drawing.Imaging

   4:  Imports System.IO

   5:   

   6:  <Serializable()> _

   7:  Public Class SerializableImage

   8:      Implements ISerializable

   9:   

  10:      Private _master As MasterEnum = MasterEnum.Image

  11:      Private _imageBuffer As Byte()

  12:      Private _image As Image

  13:      Private _serializationFormat As ImageFormat = ImageFormat.Png

  14:   

  15:      Public Property Image() As Image

  16:          Get

  17:              If _master <> MasterEnum.Image Then

  18:                  CreateImageFromBuffer()

  19:              End If

  20:              Return _image

  21:          End Get

  22:          Set(ByVal value As Image)

  23:              If (value Is _image) Then Return

  24:              _image = value

  25:              ‘The image becomes the master once the setter is used

  26:              _master = MasterEnum.Image

  27:              _imageBuffer = Nothing

  28:          End Set

  29:      End Property

  30:   

  31:      Private Sub CreateImageFromBuffer()

  32:          ‘Once this method is called, the image becomes the master

  33:          _master = MasterEnum.Image

  34:          ‘Check if there is a buffer

  35:          If _imageBuffer Is Nothing OrElse _imageBuffer.Length = 0 Then

  36:              Image = Nothing

  37:          Else

  38:              ‘http://support.microsoft.com/?id=814675

  39:              Using s As New MemoryStream(_imageBuffer)

  40:                  If Not s Is System.IO.Stream.Null Then

  41:                      Dim tempImage As Image = _

  42:                          DirectCast(Bitmap.FromStream(s), Bitmap)

  43:                      Image = New Bitmap(tempImage)

  44:                      Dim g As Graphics = Graphics.FromImage(tempImage)

  45:                      g.DrawImage(Image, New PointF(0, 0))

  46:                      g.Dispose()

  47:                      tempImage.Dispose()

  48:                  End If

  49:                  s.Close()

  50:              End Using

  51:          End If

  52:      End Sub

  53:   

  54:      Private Property ImageBuffer() As Byte()

  55:          Get

  56:              Select Case _master

  57:                  Case MasterEnum.Image

  58:                      ‘Used for serialization

  59:                      Return CreateBufferFromImage()

  60:                  Case MasterEnum.Buffer

  61:                      Return _imageBuffer

  62:              End Select

  63:              Return _imageBuffer

  64:          End Get

  65:          Set(ByVal value As Byte())

  66:              If (value Is _imageBuffer) Then Return

  67:              _imageBuffer = value

  68:              ‘The Buffer becomes the master

  69:              _master = MasterEnum.Buffer

  70:              _image = Nothing

  71:          End Set

  72:      End Property

  73:   

  74:      Private Function CreateBufferFromImage() As Byte()

  75:          If _image Is Nothing Then Return Nothing

  76:          ‘Convert the image to a byte array using the serialization format

  77:          Using stream As New MemoryStream

  78:              _image.Save(stream, SerializationFormat)

  79:              Dim result As Byte() = stream.ToArray()

  80:              stream.Close()

  81:              Return result

  82:          End Using

  83:      End Function

  84:   

  85:      Public Property SerializationFormat() As ImageFormat

  86:          Get

  87:              Return _serializationFormat

  88:          End Get

  89:          Set(ByVal value As ImageFormat)

  90:              _serializationFormat = value

  91:          End Set

  92:      End Property

  93:   

  94:      Public Sub New()

  95:   

  96:      End Sub

  97:   

  98:      Public Sub New(ByVal image As Image)

  99:          Me.Image = image

 100:      End Sub

 101:   

 102:      Public Sub New(ByVal record As IDataRecord, ByVal fieldIndex As Integer)

 103:          Load(record, fieldIndex)

 104:      End Sub

 105:   

 106:      Public Sub New(ByVal record As IDataRecord, ByVal fieldName As String)

 107:          Load(record, fieldName)

 108:      End Sub

 109:   

 110:      Private Sub Load(ByVal record As IDataRecord, ByVal fieldName As String)

 111:          If record Is Nothing Then Throw New ArgumentNullException(“record”)

 112:          Load(record, record.GetOrdinal(fieldName))

 113:      End Sub

 114:   

 115:      Private Sub Load(ByVal record As IDataRecord, ByVal fieldIndex As Integer)

 116:          If record Is Nothing Then Throw New ArgumentNullException(“record”)

 117:          If record.IsDBNull(fieldIndex) Then Return

 118:          ImageBuffer = DirectCast(record.GetValue(fieldIndex), Byte())

 119:      End Sub

 120:   

 121:      Public Sub New(ByVal info As SerializationInfo, _

 122:          ByVal context As StreamingContext)

 123:          ‘Image

 124:          Dim data As Byte() = _

 125:              DirectCast(info.GetValue(“image”, GetType(Byte())), Byte())

 126:          If data IsNot Nothing AndAlso data.Length > 0 Then

 127:              ‘http://support.microsoft.com/?id=814675

 128:              Using s As New MemoryStream(data)

 129:                  If Not s Is System.IO.Stream.Null Then

 130:                      Dim tempImage As Image = _

 131:                          DirectCast(Bitmap.FromStream(s), Bitmap)

 132:                      Image = New Bitmap(tempImage)

 133:                      Dim g As Graphics = Graphics.FromImage(tempImage)

 134:                      g.DrawImage(Image, New PointF(0, 0))

 135:                      g.Dispose()

 136:                      tempImage.Dispose()

 137:                  End If

 138:                  s.Close()

 139:              End Using

 140:          End If

 141:      End Sub

 142:   

 143:      Public Sub GetObjectData(ByVal info As SerializationInfo, +

 144:          ByVal context As StreamingContext) Implements ISerializable.GetObjectData

 145:          info.AddValue(“image”, ImageBuffer, GetType(Byte()))

 146:      End Sub

 147:   

 148:      Private Enum MasterEnum

 149:          Buffer

 150:          Image

 151:      End Enum

 152:   

 153:  End Class