Updated: September 2008
Encapsulates a metadata property to be included in an image file. Not inheritable.
Assembly: System.Drawing (in System.Drawing.dll)
The data consists of: an identifier, the length (in bytes) of the property, the property type, and a pointer to the property value.
A is not intended to be used as a stand-alone object. A object is intended to be used by classes that are derived from Image. A object is used to retrieve and to change the metadata of existing image files, not to create the metadata. Therefore, the class does not have a defined Public constructor, and you cannot create an instance of a object.
To work around the absence of a Public constructor, use an existing object instead of creating a new instance of the class. For more information, see Image.GetPropertyItem.
The following code example demonstrates how to read and display the metadata in an image file using the class and the Image.PropertyItems property.
This example is designed to be used in a Windows Form that imports the System.Drawing.Imaging namespace. Paste the code into the form and change the path to fakePhoto.jpg to point to an image file on your system. Call the ExtractMetaData method when handling the form's Paint event, passing e as PaintEventArgs.
Private Sub ExtractMetaData(ByVal e As PaintEventArgs) Try 'Create an Image object. Dim theImage As Image = New Bitmap("c:\fakePhoto.jpg") 'Get the PropertyItems property from image. Dim propItems As PropertyItem() = theImage.PropertyItems 'Set up the display. Dim font As New font("Arial", 10) Dim blackBrush As New SolidBrush(Color.Black) Dim X As Integer = 0 Dim Y As Integer = 0 'For each PropertyItem in the array, display the id, type, and length. Dim count As Integer = 0 Dim propItem As PropertyItem For Each propItem In propItems e.Graphics.DrawString("Property Item " + count.ToString(), _ font, blackBrush, X, Y) Y += font.Height e.Graphics.DrawString(" iD: 0x" & propItem.Id.ToString("x"), _ font, blackBrush, X, Y) Y += font.Height e.Graphics.DrawString(" type: " & propItem.Type.ToString(), _ font, blackBrush, X, Y) Y += font.Height e.Graphics.DrawString(" length: " & propItem.Len.ToString() & _ " bytes", font, blackBrush, X, Y) Y += font.Height count += 1 Next propItem font.Dispose() Catch ex As ArgumentException MessageBox.Show("There was an error. Make sure the path to the image file is valid.") End Try End Sub
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.