Graphics.AddMetafileComment(Byte[]) 方法

定义

向当前 Metafile添加注释。

public:
 void AddMetafileComment(cli::array <System::Byte> ^ data);
public void AddMetafileComment (byte[] data);
member this.AddMetafileComment : byte[] -> unit
Public Sub AddMetafileComment (data As Byte())

参数

data
Byte[]

包含注释的字节数组。

示例

下面的代码示例旨在与 Windows 窗体一起使用,它需要 PaintEventArgse,这是 Paint 事件处理程序的参数,以及 thisForm示例的 Form。 该代码执行以下操作:

  • 创建临时 Graphics 以创建图元文件,并获取其设备上下文的句柄 hdc

  • 使用 hdc创建新的图元文件。

  • 创建一个 Graphics,用于显示 Metafile中的图元文件。

  • 将矩形绘制到图元文件。

  • 向图元文件添加注释。

  • 释放图元文件 Graphics,这将关闭图元文件。

  • 释放图元文件。

  • 释放临时 hdc

  • 释放临时 Graphics

  • 从之前创建的文件创建第二个图元文件。

  • 将图元文件绘制到屏幕。

  • 释放图元文件。

private:
   [SecurityPermission(SecurityAction::Demand, Flags = SecurityPermissionFlag::UnmanagedCode)]            
   void AddMetafileCommentBytes( PaintEventArgs^ e )
   {
      // Create temporary Graphics object for metafile
      //  creation and get handle to its device context.
      Graphics^ newGraphics = this->CreateGraphics();
      IntPtr hdc = newGraphics->GetHdc();

      // Create metafile object to record.
      Metafile^ metaFile1 = gcnew Metafile( "SampMeta.emf",hdc );

      // Create graphics object to record metaFile.
      Graphics^ metaGraphics = Graphics::FromImage( metaFile1 );

      // Draw rectangle in metaFile.
      metaGraphics->DrawRectangle( gcnew Pen( Color::Black,5.0f ), 0, 0, 100, 100 );

      // Create comment and add to metaFile.
      array<Byte>^metaComment = {(Byte)'T',(Byte)'e',(Byte)'s',(Byte)'t'};
      metaGraphics->AddMetafileComment( metaComment );

      // Dispose of graphics object.
      delete metaGraphics;

      // Dispose of metafile.
      delete metaFile1;

      // Release handle to temporary device context.
      newGraphics->ReleaseHdc( hdc );

      // Dispose of scratch graphics object.
      delete newGraphics;

      // Create existing metafile object to draw.
      Metafile^ metaFile2 = gcnew Metafile( "SampMeta.emf" );

      // Draw metaFile to screen.
      e->Graphics->DrawImage( metaFile2, Point(0,0) );

      // Dispose of metafile.
      delete metaFile2;
   }
private void AddMetafileCommentBytes(PaintEventArgs e)
{
    // Create temporary Graphics object for metafile
    //  creation and get handle to its device context.
    Graphics newGraphics = this.CreateGraphics();
    IntPtr hdc = newGraphics.GetHdc();
             
    // Create metafile object to record.
    Metafile metaFile1 = new Metafile("SampMeta.emf", hdc);
             
    // Create graphics object to record metaFile.
    Graphics metaGraphics = Graphics.FromImage(metaFile1);
             
    // Draw rectangle in metaFile.
    metaGraphics.DrawRectangle(new Pen(Color.Black, 5), 0, 0, 100, 100);
             
    // Create comment and add to metaFile.
    byte[] metaComment = {(byte)'T', (byte)'e', (byte)'s', (byte)'t'};
    metaGraphics.AddMetafileComment(metaComment);
             
    // Dispose of graphics object.
    metaGraphics.Dispose();
             
    // Dispose of metafile.
    metaFile1.Dispose();
             
    // Release handle to temporary device context.
    newGraphics.ReleaseHdc(hdc);
             
    // Dispose of scratch graphics object.
    newGraphics.Dispose();
             
    // Create existing metafile object to draw.
    Metafile metaFile2 = new Metafile("SampMeta.emf");
             
    // Draw metaFile to screen.
    e.Graphics.DrawImage(metaFile2, new Point(0, 0));
             
    // Dispose of metafile.
    metaFile2.Dispose();
}
Private Sub AddMetafileCommentBytes(ByVal e As PaintEventArgs)

    ' Create temporary graphics object for metafile
    ' creation and get handle to its device context.
    Dim newGraphics As Graphics = Me.CreateGraphics()
    Dim hdc As IntPtr = newGraphics.GetHdc()

    ' Create metafile object to record.
    Dim metaFile1 As New Metafile("SampMeta.emf", hdc)

    ' Create graphics object to record metaFile.
    Dim metaGraphics As Graphics = Graphics.FromImage(metaFile1)

    ' Draw rectangle in metaFile.
    metaGraphics.DrawRectangle(New Pen(Color.Black, 5), 0, 0, 100, 100)

    ' Create comment and add to metaFile.
    Dim metaComment As Byte() = {CByte("T"), CByte("e"), CByte("s"), _
    CByte("t")}
    metaGraphics.AddMetafileComment(metaComment)

    ' Dispose of graphics object.
    metaGraphics.Dispose()

    ' Dispose of metafile.
    metaFile1.Dispose()

    ' Release handle to scratch device context.
    newGraphics.ReleaseHdc(hdc)

    ' Dispose of scratch graphics object.
    newGraphics.Dispose()

    ' Create existing metafile object to draw.
    Dim metaFile2 As New Metafile("SampMeta.emf")

    ' Draw metaFile to screen.
    e.Graphics.DrawImage(metaFile2, New Point(0, 0))

    ' Dispose of metafile.
    metaFile2.Dispose()
End Sub

注解

仅当此 GraphicsMetafile关联时,此方法才有效。

适用于