图表转为图像

渲染图表

Aspose.Cells APIs支持将Excel图表转换为图像格式，无需额外的工具或应用程序。为了提供渲染支持，Chart类已公开了ToImage多种方法，最好地满足应用程序的需求。

将图表渲染为图像

Chart.ToImage方法具有多种重载，支持简单和高级渲染。如果应用程序的要求是在其默认尺寸下渲染图表，我们建议您使用Chart.ToImage方法。

// For complete examples and data files, please go to https://github.com/aspose-cells/Aspose.Cells-for-.NET
// The path to the documents directory.
string dataDir = RunExamples.GetDataDir(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

// Instantiating a Workbook object
Workbook workbook = new Workbook();
// Adding a new worksheet to the Workbook
int sheetIndex = workbook.Worksheets.Add();
// Obtaining the reference of the newly added worksheet by passing its index to WorksheetCollection
Worksheet worksheet = workbook.Worksheets[sheetIndex];

// Adding sample values to cells
worksheet.Cells["A1"].PutValue(50);
worksheet.Cells["A2"].PutValue(100);
worksheet.Cells["A3"].PutValue(150);
worksheet.Cells["B1"].PutValue(4);
worksheet.Cells["B2"].PutValue(20);
worksheet.Cells["B3"].PutValue(50);

// Adding a chart to the worksheet
int chartIndex = worksheet.Charts.Add(Aspose.Cells.Charts.ChartType.Column, 5, 0, 15, 5);
// Accessing the instance of the newly added chart
Aspose.Cells.Charts.Chart chart = worksheet.Charts[chartIndex];
// Adding Series Collection (chart data source) to the chart ranging from "A1" cell to "B3"
chart.NSeries.Add("A1:B3", true);
            
// Converting chart to image
chart.ToImage(dataDir + "chartEMF_out.emf", ImageType.Emf);

// Converting chart to Bitmap
System.Drawing.Bitmap bitmap = chart.ToImage();
bitmap.Save(dataDir + "chartBMP_out.bmp", System.Drawing.Imaging.ImageFormat.Bmp);

还可以使用高级设置将图表渲染为图像。Aspose.Cells APIs公开了Chart.ToImage方法的重载版本，可接受ImageOrPrintOptions的实例，并允许指定参数，如分辨率、平滑模式、图像格式等。

// For complete examples and data files, please go to https://github.com/aspose-cells/Aspose.Cells-for-.NET
// The path to the documents directory.
string dataDir = RunExamples.GetDataDir(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

// Instantiating a Workbook object
Workbook workbook = new Workbook();
// Adding a new worksheet to the Workbook
int sheetIndex = workbook.Worksheets.Add();
// Obtaining the reference of the newly added worksheet by passing its index to WorksheetCollection
Worksheet worksheet = workbook.Worksheets[sheetIndex];

// Adding sample values to cells
worksheet.Cells["A1"].PutValue(50);
worksheet.Cells["A2"].PutValue(100);
worksheet.Cells["A3"].PutValue(150);
worksheet.Cells["B1"].PutValue(4);
worksheet.Cells["B2"].PutValue(20);
worksheet.Cells["B3"].PutValue(50);

// Adding a chart to the worksheet
int chartIndex = worksheet.Charts.Add(Aspose.Cells.Charts.ChartType.Column, 5, 0, 15, 5);
// Accessing the instance of the newly added chart
Aspose.Cells.Charts.Chart chart = worksheet.Charts[chartIndex];
// Adding Series Collection (chart data source) to the chart ranging from "A1" cell to "B3"
chart.NSeries.Add("A1:B3", true);

// Create an instance of ImageOrPrintOptions and set a few properties
ImageOrPrintOptions options = new ImageOrPrintOptions()
{
    VerticalResolution = 300,
    HorizontalResolution = 300,
    SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias
};
// Convert chart to image with additional settings
chart.ToImage(dataDir + "chartPNG_out.png", options);

支持的图表类型的渲染

目前有一些不支持渲染的图表类型。这些图表类型在下表的Supported列中包含N。

图表类型	图表子类型	支持
Column	Column	Y
	ColumnStacked	Y
	Column100PercentStacked	Y
	Column3DClustered	Y
	Column3DStacked	Y
	Column3D100PercentStacked	Y
	Column3D	Y
Bar	Bar	Y
	BarStacked	Y
	Bar100PercentStacked	Y
	Bar3DClustered	Y
	Bar3DStacked	Y
	Bar3D100PercentStacked	Y
Line	Line	Y
	LineStacked	Y
	Line100PercentStacked	Y
	LineWithDataMarkers	Y
	LineStackedWithDataMarkers	Y
	Line100PercentStackedWithDataMarkers	Y
	Line3D	Y
Pie	Pie	Y
	Pie3D	Y
	PiePie	Y
	PieExploded	Y
	Pie3DExploded	Y
	PieBar	Y
Scatter	Scatter	Y
	ScatterConnectedByCurvesWithDataMarker	Y
	ScatterConnectedByCurvesWithoutDataMarker	Y
	ScatterConnectedByLinesWithDataMarker	Y
	ScatterConnectedByLinesWithoutDataMarker	Y
Area	Area	Y
	AreaStacked	Y
	Area100PercentStacked	Y
	Area3D	Y
	Area3DStacked	Y
	Area3D100PercentStacked	Y
Doughnut	Doughnut	Y
	DoughnutExploded	Y
Radar	Radar	Y
	RadarWithDataMarkers	Y
	RadarFilled	Y
Surface	Surface3D	N
	SurfaceWireframe3D	N
	SurfaceContour	N
	SurfaceContourWireframe	N
Bubble	Bubble	Y
	Bubble3D	N
Stock	StockHighLowClose	Y
	StockOpenHighLowClose	Y
	StockVolumeHighLowClose	Y
	StockVolumeOpenHighLowClose	Y
Cylinder	Cylinder	Y
	CylinderStacked	Y
	Cylinder100PercentStacked	Y
	CylindricalBar	Y
	CylindricalBarStacked	Y
	CylindricalBar100PercentStacked	Y
	CylindricalColumn3D	Y
Cone	Cone	Y
	ConeStacked	Y
	Cone100PercentStacked	Y
	ConicalBar	Y
	ConicalBarStacked	Y
	ConicalBar100PercentStacked	Y
	ConicalColumn3D	Y
Pyramid	Pyramid	Y
	PyramidStacked	Y
	Pyramid100PercentStacked	Y
	PyramidBar	Y
	PyramidBarStacked	Y
	PyramidBar100PercentStacked	Y
	PyramidColumn3D	Y
BoxWhisker	BoxWhisker	Y
Funnel	Funnel	Y
ParetoLine	ParetoLine	Y
Sunburst	Sunburst	Y
Treemap	Treemap	Y
Waterfall	Waterfall	Y
Histogram	Histogram	Y
Map	Map	N

如果尝试将不受支持的图表类型渲染为图像或PDF，则可能会得到大小为0的图像或空白PDF。

高级主题

• 将图表转换为PDF