渲染报告质量EMF与PDF

Question

我在渲染SSRS serverreport并从代码中打印时遇到了困难。

虽然渲染成功并且打印报告，但图形质量的结果很差。该报告本身具有高分辨率的6kx1k GIF图像作为徽标。

我在下面制作了图片来说明使用EMF与PDF进行渲染之间的区别：

正如您所看到的那样，字体看起来很棒（没有像素化），而且在PDF徽标中渲染效果很好。但是，EMF版本的质量很差，因为您可以在徽标的边缘看到。

有人遇到过这个问题并解决了吗？

我正在运行SQL Server 2008R2 SP2（10.50.4000）

使用EMF呈现报告的代码

public List<byte[]> Render()
{
    // Setting credentials and reporting services uri
    ReportExecutionService reportService = new ReportExecutionService
        {
            Credentials = _credentials,
            Url = Settings.Default.ReportingService
        };

    // Prepare report parameter.
    ExecutionHeader execHeader = new ExecutionHeader();
    reportService.ExecutionHeaderValue = execHeader;
    reportService.LoadReport(_report, null);
    reportService.SetExecutionParameters(_parameters.ToArray(), "en-us");

    // Render
    bool startup = true;
    List<byte[]> streams = new List<byte[]>();
    int numberOfPages = 0;
    byte[] result = null;
    while (startup || result.Length > 0)
    {
        startup = false;
        string devInfo = String.Format(@"<DeviceInfo><OutputFormat>EMF</OutputFormat><PrintDpiX>150</PrintDpiX><PrintDpiY>150</PrintDpiY><StartPage>{0}</StartPage></DeviceInfo>", numberOfPages + 1);
        string encoding, mimeType, extension;
        string[] streamIDs = null;
        Warning[] warnings = null;
        result = reportService.Render("IMAGE", devInfo, out extension, out encoding, out mimeType, out warnings, out streamIDs);

        if (result.Length > 0)
        {
            streams.Add(result);
        }
        numberOfPages++;
    }
    return streams;
}

这是printdocument实现

public class PrintReport : PrintDocument
{
    private int _currentPage;
    private  List<byte[]> _pages;

    public PrintReport()
    {
    }

    public List<byte[]> Pages
    {
        get { return _pages; }
        set { _pages = value; }
    }

    protected override void OnBeginPrint(PrintEventArgs e)
    {
        base.OnBeginPrint(e);
        _currentPage = 0;
    }

    protected override void OnPrintPage(PrintPageEventArgs e)
    {
        base.OnPrintPage(e);

        Stream pageToPrint = new MemoryStream(_pages[_currentPage]);
        pageToPrint.Position = 0;

        // Load each page into a Metafile to draw it.
        using (Metafile pageMetaFile = new Metafile(pageToPrint))
        {
            Rectangle adjustedRect = new Rectangle(
                    e.PageBounds.Left - (int)e.PageSettings.HardMarginX,
                    e.PageBounds.Top - (int)e.PageSettings.HardMarginY,
                    e.PageBounds.Width,
                    e.PageBounds.Height);

            // Draw a white background for the report
            e.Graphics.FillRectangle(Brushes.White, adjustedRect);

            // Draw the report content
            e.Graphics.DrawImage(pageMetaFile, adjustedRect);

            // Prepare for next page.  Make sure we haven't hit the end.
            _currentPage++;
            e.HasMorePages = _currentPage < _pages.Count;
        }
    }

    protected override void OnQueryPageSettings(QueryPageSettingsEventArgs e)
    {
        e.PageSettings = (PageSettings)PrinterSettings.DefaultPageSettings.Clone();
    }
}