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C-如何打印纵横比/整页

Alex Gordon · 技术社区 · 14 年前

我正在打印图表控件,单击按钮:

chart1.SaveImage(ms, ChartImageFormat.Bmp);
Bitmap bm = new Bitmap(ms);

PrintDocument doc = new PrintDocument();
doc.PrintPage += (s, ev) =>
{
    ev.Graphics.DrawImage(bm, Point.Empty); // adjust this to put the image elsewhere
    ev.HasMorePages = false;
};
doc.DefaultPageSettings.Landscape = true;

doc.Print();

如何强制它打印控件以使其适合页面大小(保留纵横比)?

3 回复 | 直到 6 年前

Peter Mortensen icecrime 12 年前

至少有两种不同的方法可以做到这两个方面 包括缩放要打印的图像以适应页面大小 所选打印机的:

1)使用 .NET 设施 post ):

    private void printDocument1_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
    {
        Image i = pictureBox1.Image;

        float newWidth = i.Width * 100 / i.HorizontalResolution;
        float newHeight = i.Height * 100 / i.VerticalResolution;

        float widthFactor = newWidth / e.MarginBounds.Width;
        float heightFactor = newHeight / e.MarginBounds.Height;

        if(widthFactor>1 | heightFactor > 1)
        {
            if(widthFactor > heightFactor)
            {
                newWidth = newWidth / widthFactor;
                newHeight = newHeight / widthFactor;
            }
            else
            {
                newWidth = newWidth / heightFactor;
                newHeight = newHeight / heightFactor;
            }
        }
        e.Graphics.DrawImage(i, 0, 0, (int)newWidth, (int)newHeight);
    }
}

2) P/Invoke'ing Windows API 来自gdi和flat gdi的调用(这要复杂得多,但速度更快,您可以传递位图文件的纯字节数组(将文件读取为byte[]),如果需要此代码,请向我提供电子邮件):

  private static extern bool ClosePrinter(IntPtr hPrinter);
  private static extern bool OpenPrinter([MarshalAs(UnmanagedType.LPStr)] string szPrinter, out IntPtr hPrinter, IntPtr pd);
  private static extern int SetJob(IntPtr hPrinter, int JobId, int Level, ref byte pJob, int Command_Renamed);
  private static extern int GdiplusStartup(out IntPtr token, ref StartupInput input, out StartupOutput output);
  private static extern int GdiplusShutdown(IntPtr token);
  internal static extern int GdipLoadImageFromStream([In, MarshalAs(UnmanagedType.Interface)]IStream stream, out IntPtr image);
  internal static extern int GdipDisposeImage(IntPtr image);
  static internal extern int GdipCreateFromHDC2(IntPtr hDC, IntPtr hDevice, out IntPtr graphics);
  static internal extern int GdipDeleteGraphics(IntPtr graphics);
  static internal extern int GdipReleaseDC(IntPtr graphics, IntPtr hdc);
  internal static extern int GdipGetImageDimension(IntPtr image, out float width, out float height);
  internal static extern int GdipGetDpiX(IntPtr graphics, out float dpi);
  internal static extern int GdipGetDpiY(IntPtr graphics, out float dpi);
  static internal extern int GdipDrawImageRectI(IntPtr graphics, IntPtr image, int x, int y, int width, int height);
  private static extern IntPtr CreateDC([MarshalAs(UnmanagedType.LPStr)] string lpszDriver, [MarshalAs(UnmanagedType.LPStr)] string lpszDevice, [MarshalAs(UnmanagedType.LPStr)] string lpszOutput, IntPtr lpInitData);
  private static extern bool DeleteDC(IntPtr hdc);
  private static extern int StartDoc(IntPtr hdc, DOCINFO lpdi);
  private static extern int EndDoc(IntPtr hdc);
  private static extern int StartPage(IntPtr hdc);
  private static extern int EndPage(IntPtr hdc);
  private static extern int GetDeviceCaps(IntPtr hdc, int nIndex);

Dave Cousineau 9 年前

我就是这么做的。令人恼火的是,图表控件将只绘制与屏幕上大小相同的内容。我发现解决这个问题的唯一方法是手动调整大小。然后,由于它可能不喜欢在窗体上调整大小,这也涉及到将其临时从窗体中删除。

所有这些,我最终得到了这样的结果:

Chart ChartBox { get; private set; }

...

var oldParent = ChartBox.Parent;
var oldSize = ChartBox.Size;

ChartBox.Parent = null;
ChartBox.Size = new Size(width, height);

ChartBox.Printing.Print();

ChartBox.Parent = oldParent;
ChartBox.Size = oldSize;

根据窗体的不同,您可能还需要保存和恢复图表控件的其他属性。

Adeel Kamran 6 年前

试试这个代码:

e.Graphics.DrawImage(img, e.Graphics.VisibleClipBounds);