Metafile Class
Defines a graphic metafile. A metafile contains records that describe a sequence of graphics operations that can be recorded (constructed) and played back (displayed). This class is not inheritable.

Namespace: System.Drawing.Imaging
Assembly: System.Drawing (in system.drawing.dll)

Syntax

Visual Basic (Declaration)
<SerializableAttribute> _
Public NotInheritable Class Metafile
    Inherits Image
Visual Basic (Usage)
Dim instance As Metafile
C#
[SerializableAttribute] 
public sealed class Metafile : Image
C++
[SerializableAttribute] 
public ref class Metafile sealed : public Image
J#
/** @attribute SerializableAttribute() */ 
public final class Metafile extends Image
JScript
SerializableAttribute 
public final class Metafile extends Image
XAML
Not applicable.
Remarks

When you use the Save method to save a graphic image as a Windows Metafile Format (WMF) or Enhanced Metafile Format (EMF) file, the resulting file is saved as a Portable Network Graphics (PNG) file instead. This behavior occurs because the GDI+ component of the .NET Framework does not have an encoder that you can use to save files as .wmf or .emf files.

Example

The following code example demonstrates how to create a Metafile and use the PlayRecord method.

Visual Basic
Imports System
Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.Windows.Forms
' for Marshal.Copy
Imports System.Runtime.InteropServices


Public Class Form1
    Inherits Form
    Private metafile1 As Metafile
    Private metafileDelegate As Graphics.EnumerateMetafileProc
    Private destPoint As Point
    
    Public Sub New() 
        metafile1 = New Metafile("C:\test.wmf")
        metafileDelegate = New Graphics.EnumerateMetafileProc(AddressOf MetafileCallback)
        destPoint = New Point(20, 10)
    
    End Sub
    
    Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs) 
        e.Graphics.EnumerateMetafile(metafile1, destPoint, metafileDelegate)
    
    End Sub
    
    Private Function MetafileCallback(ByVal recordType As _
        EmfPlusRecordType, ByVal flags As Integer, ByVal dataSize As Integer, _
        ByVal data As IntPtr, ByVal callbackData As PlayRecordCallback) As Boolean

        Dim dataArray As Byte() = Nothing
        If data <> IntPtr.Zero Then

            ' Copy the unmanaged record to a managed byte buffer 
            ' that can be used by PlayRecord.
            dataArray = New Byte(dataSize) {}
            Marshal.Copy(data, dataArray, 0, dataSize)
        End If

        metafile1.PlayRecord(recordType, flags, dataSize, dataArray)
        Return True

    End Function
    
    Shared Sub Main() 
        Application.Run(New Form1())
    End Sub

End Class
C#
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Windows.Forms;

// for Marshal.Copy
using System.Runtime.InteropServices; 

public class Form1 : Form
{
    private Metafile metafile1;
    private Graphics.EnumerateMetafileProc metafileDelegate;
    private Point destPoint;
    public Form1()
    {
        metafile1 = new Metafile(@"C:\Test.wmf");
        metafileDelegate = new Graphics.EnumerateMetafileProc(MetafileCallback);
        destPoint = new Point(20, 10);
    }
    protected override void OnPaint(PaintEventArgs e)
    {
        e.Graphics.EnumerateMetafile(metafile1, destPoint, metafileDelegate);
    }
    private bool MetafileCallback(
       EmfPlusRecordType recordType,
       int flags,
       int dataSize,
       IntPtr data,
       PlayRecordCallback callbackData)
    {
        byte[] dataArray = null;
        if (data != IntPtr.Zero)
        {
            // Copy the unmanaged record to a managed byte buffer 
            // that can be used by PlayRecord.
            dataArray = new byte[dataSize];
            Marshal.Copy(data, dataArray, 0, dataSize);
        }

        metafile1.PlayRecord(recordType, flags, dataSize, dataArray);

        return true;
    }

    static void Main()
    {
        Application.Run(new Form1());
    }
}
Inheritance Hierarchy

System.Object
   System.MarshalByRefObject
     System.Drawing.Image
      System.Drawing.Imaging.Metafile
Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Platforms

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

Version Information

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0
See Also

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