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我想从 WPF 控件创建位图。我在这个论坛中看到了一些示例（最重要的是：将“不可见”的 WPF 控件渲染到位图图像），但只有当 WPF 控件已经显示在屏幕上时，它们才能很好地渲染。

我必须在模型中创建一个控件以将位图结果关联到他的内部位图字段。

我按照示例进入了上面的线程，但结果是一个位图，其中只有控件的一部分内容（好像没有完全渲染）。

如何在图像渲染采集之前执行完整的渲染？

这是我的源代码：

if( spChart == null){
    String s = "<SparrowChart xmlns=\"http://sparrowtoolkit.codeplex.com/wpf\">" +
                          "    <SparrowChart.XAxis>" +
                          "        <LinearXAxis/>" +
                          "    </SparrowChart.XAxis>" +
                          "    <SparrowChart.YAxis>" +
                          "        <LinearYAxis/>" +
                          "    </SparrowChart.YAxis>" +
                          "</SparrowChart>";
    System.IO.StringReader stringReader = new System.IO.StringReader(s);
    System.Xml.XmlReader xmlReader;
                xmlReader = System.Xml.XmlReader.Create(stringReader);
    spChart = (Sparrow.Chart.SparrowChart)System.Windows.Markup.XamlReader.Load(xmlReader);
    spChart.XAxes[0].MinValue = 0;
    spChart.XAxes[0].MaxValue = 10;
    spChart.YAxes[0].MinValue = 0;
    spChart.YAxes[0].MaxValue = 10;
    spChart.Series.Clear();
} else {
    spChart.Series.Clear();
}

List<System.Drawing.PointF> points = new List<System.Drawing.PointF> {new System.Drawing.PointF(3, 7),
                                                                      new System.Drawing.PointF(5, 2),
                                                                      new System.Drawing.PointF(8, 4),
                                                                      new System.Drawing.PointF(4, 6)};
Sparrow.Chart.SeriesBase LS = new Sparrow.Chart.SplineSeries();
foreach(System.Drawing.PointF x in points) {
    Sparrow.Chart.DoublePoint newPoint = new Sparrow.Chart.DoublePoint();
    newPoint.Data=x.X;
    newPoint.Value=x.Y;
}
spChart.Series.Add(LS);
LS = new Sparrow.Chart.ScatterSeries();
foreach(System.Drawing.PointF x in points) {
    Sparrow.Chart.DoublePoint newPoint = new Sparrow.Chart.DoublePoint();
    newPoint.Data=x.X;
    newPoint.Value=x.Y;
}
spChart.Series.Add(LS);
spChart.Measure(new System.Windows.Size(Double.PositiveInfinity, Double.PositiveInfinity));
spChart.Arrange(new System.Windows.Rect(new System.Windows.Size(1000, 1000)));
spChart.UpdateLayout();

RenderTargetBitmap rtb = new RenderTargetBitmap((int)SpChart.ActualWidth, (int)SpChart.ActualHeight, 96, 96, Windows.Media.PixelFormats.Pbgra32);
rtb.Render(spChart);
PngBitmapEncoder png = new PngBitmapEncoder();
png.Frames.Add(BitmapFrame.Create(rtb));
MemoryStream stream = New MemoryStream();
png.Save(stream);
Bitmap tmpBitmap = new Bitmap(Image.FromStream(stream));
bitmapToRender = MyBitmap.Clone();
MyBitmap.Dispose();

谢谢

卢西奥

4

1 回答 1

1

对我来说，这个工作：

Size size = new Size(432, 460);
frameworkElement.Measure(size);
frameworkElement.Arrange(new Rect(new Point(), size));
frameworkElement.UpdateLayout();

RenderTargetBitmap renderTargetBitmap = new RenderTargetBitmap((int)frameworkElement.ActualWidth, (int)frameworkElement.ActualHeight, 96, 96, PixelFormats.Pbgra32);
renderTargetBitmap.Render(frameworkElement);

FormatConvertedBitmap monoBitmap = new FormatConvertedBitmap(renderTargetBitmap, PixelFormats.BlackWhite, null, 0);

BmpBitmapEncoder bmpImage = new BmpBitmapEncoder();
bmpImage.Frames.Add(BitmapFrame.Create(monoBitmap));

byte[] bmpData;

using (MemoryStream buffer = new MemoryStream())
{
    bmpImage.Save(buffer);
    bmpData = buffer.ToArray();
}

抱歉导致单色位图，这正是我使用的。结果，这可以简单地转换为任何位图类型。

于 2015-02-01T18:32:28.723 回答