使用 PHP 在演示文稿中管理图表数据标签

本页内容简介

了解如何使用 Aspose.Slides for PHP via Java 在 PowerPoint 演示文稿中添加和格式化图表数据标签，以创建更具吸引力的幻灯片。

介绍

数据标签显示图表系列和单个数据点的信息，帮助读者识别数值并理解图表。本文说明如何格式化数值、显示百分比、读取标签文本、控制轴最大值之外的标签、调整分类坐标轴标签间距以及定位饼图标签。

设置图表数据标签的数据精度

使用 setNumberFormatOfValues 来格式化系列数值。此示例创建一个默认数据的折线图，显示其数据表，并为第一系列启用数值标签。格式 #,##0.00 显示千位分隔符和两位小数，而不更改底层数值。

use aspose\slides\Presentation;
use aspose\slides\ChartType;
use aspose\slides\SaveFormat;

$presentation = new Presentation();
try {
    $slide = $presentation->getSlides()->get_Item(0);

    $chart = $slide->getShapes()->addChart(ChartType::Line, 50, 50, 450, 300);
    $chart->setDataTable(true);

    $series = $chart->getChartData()->getSeries()->get_Item(0);
    $series->setNumberFormatOfValues("#,##0.00");
    $series->getLabels()->getDefaultDataLabelFormat()->setShowValue(true);

    $presentation->save("PrecisionOfDatalabels_out.pptx", SaveFormat::Pptx);
} finally {
    $presentation->dispose();
}

若要格式化图表嵌入工作簿中的数值单元格，请参阅 Set Custom Number Formats for Workbook Cells。该示例还展示了数值标签遵循其来源单元格格式，同时保留存储的数值。

将百分比显示为标签

对于堆积柱形图，计算每个数值占其类别总和的百分比，并将文本分配给由 getTextFrameForOverriding 返回的文本框。本示例使用默认图表数据，使用 8 磅字体显示两位小数的百分比。总和为零的类别会被跳过，以避免除以零。当图表数据变化时，需要重新计算自定义标签文本。

use aspose\slides\Presentation;
use aspose\slides\ChartType;
use aspose\slides\Portion;
use aspose\slides\SaveFormat;

$presentation = new Presentation();
try {
    $slide = $presentation->getSlides()->get_Item(0);

    $chart = $slide->getShapes()->addChart(ChartType::StackedColumn, 20, 20, 400, 400);

    $categoryCount = java_values($chart->getChartData()->getCategories()->size());
    $categoryTotals = array_fill(0, $categoryCount, 0.0);
    for ($k = 0; $k < $categoryCount; $k++) {
        for ($i = 0; $i < java_values($chart->getChartData()->getSeries()->size()); $i++) {
            $series = $chart->getChartData()->getSeries()->get_Item($i);
            $pointValue = java_values($series->getDataPoints()->get_Item($k)->getValue()->getData());
            $categoryTotals[$k] += $pointValue;
        }
    }

    for ($x = 0; $x < java_values($chart->getChartData()->getSeries()->size()); $x++) {
        $series = $chart->getChartData()->getSeries()->get_Item($x);
        $series->getLabels()->getDefaultDataLabelFormat()->setShowLegendKey(false);

        for ($j = 0; $j < java_values($series->getDataPoints()->size()); $j++) {
            $label = $series->getDataPoints()->get_Item($j)->getLabel();
            if ($categoryTotals[$j] == 0) {
                continue;
            }

            $pointValue = java_values($series->getDataPoints()->get_Item($j)->getValue()->getData());
            $dataPointPercent = ($pointValue / $categoryTotals[$j]) * 100;

            $portion = new Portion();
            $portion->setText(sprintf("%.2F %%", $dataPointPercent));
            $portion->getPortionFormat()->setFontHeight(8);

            $label->getTextFrameForOverriding()->setText("");
            $paragraph = $label->getTextFrameForOverriding()->getParagraphs()->get_Item(0);
            $paragraph->getPortions()->add($portion);

            $label->getDataLabelFormat()->setShowValue(true);
            $label->getDataLabelFormat()->setShowSeriesName(false);
            $label->getDataLabelFormat()->setShowPercentage(false);
            $label->getDataLabelFormat()->setShowLegendKey(false);
            $label->getDataLabelFormat()->setShowCategoryName(false);
            $label->getDataLabelFormat()->setShowBubbleSize(false);
        }
    }

    $presentation->save("DisplayPercentageAsLabels_out.pptx", SaveFormat::Pptx);
} finally {
    $presentation->dispose();
}

使用图表数据标签设置百分号

当数值以分数形式存储时，使用 setNumberFormat 显示百分比。将 false 传递给 setNumberFormatLinkedToSource 以使标签格式独立于来源单元格。

此示例创建一个 100% 堆积柱形图，四个类别分别包含红色和蓝色系列。每对数值的总和为 1。标签格式 0.0% 将 0.30 显示为 30.0%，而垂直轴使用两位小数。两个系列均使用白色、10 磅的标签文本。

use aspose\slides\Presentation;
use aspose\slides\ChartType;
use aspose\slides\FillType;
use aspose\slides\SaveFormat;

$presentation = new Presentation();
try {
    $slide = $presentation->getSlides()->get_Item(0);

    $chart = $slide->getShapes()->addChart(ChartType::PercentsStackedColumn, 20, 20, 500, 400);

    $chart->getAxes()->getVerticalAxis()->setNumberFormatLinkedToSource(false);
    $chart->getAxes()->getVerticalAxis()->setNumberFormat("0.00%");

    $chart->getChartData()->getSeries()->clear();
    $chart->getChartData()->getCategories()->clear();

    $workbook = $chart->getChartData()->getChartDataWorkbook();
    $worksheetIndex = 0;
    for ($i = 0; $i < 4; $i++) {
        $categoryCell = $workbook->getCell($worksheetIndex, $i + 1, 0, "Category " . ($i + 1));
        $chart->getChartData()->getCategories()->add($categoryCell);
    }

    $colors = java("java.awt.Color");
    $seriesNames = [ "Reds", "Blues" ];
    $seriesColors = [ $colors->RED, $colors->BLUE ];
    $values = [ [ 0.30, 0.50, 0.80, 0.65 ], [ 0.70, 0.50, 0.20, 0.35 ] ];

    for ($i = 0; $i < count($seriesNames); $i++) {
        $seriesCell = $workbook->getCell($worksheetIndex, 0, $i + 1, $seriesNames[$i]);
        $series = $chart->getChartData()->getSeries()->add($seriesCell, $chart->getType());
        for ($j = 0; $j < 4; $j++) {
            $valueCell = $workbook->getCell($worksheetIndex, $j + 1, $i + 1, $values[$i][$j]);
            $series->getDataPoints()->addDataPointForBarSeries($valueCell);
        }

        $series->getFormat()->getFill()->setFillType(FillType::Solid);
        $series->getFormat()->getFill()->getSolidFillColor()->setColor($seriesColors[$i]);

        $labelFormat = $series->getLabels()->getDefaultDataLabelFormat();
        $labelFormat->setShowValue(true);
        $labelFormat->setNumberFormatLinkedToSource(false);
        $labelFormat->setNumberFormat("0.0%");
        $labelFormat->getTextFormat()->getPortionFormat()->setFontHeight(10);
        $labelFormat->getTextFormat()->getPortionFormat()->getFillFormat()->setFillType(FillType::Solid);
        $labelFormat->getTextFormat()->getPortionFormat()->getFillFormat()->getSolidFillColor()->setColor($colors->WHITE);
    }

    $presentation->save("SetDataLabelsPercentageSign_out.pptx", SaveFormat::Pptx);
} finally {
    $presentation->dispose();
}

读取数据标签的实际文本

使用 getActualLabelText 获取由数据标签设置生成的文本。这在提取报告标签、搜索演示文稿内容或验证生成的图表时非常有用。在下面的示例中，默认的 data label format 将每个类别名称、系列名称和数值组合在一起。一个点将其数值格式化为百分比，另一个使用来自 getTextFrameForOverriding 的自定义文本。

use aspose\slides\Presentation;
use aspose\slides\ChartType;

$presentation = new Presentation();
try {
    $slide = $presentation->getSlides()->get_Item(0);

    $chart = $slide->getShapes()->addChart(ChartType::ClusteredColumn, 20, 20, 500, 300);

    $chart->getChartData()->getSeries()->clear();
    $chart->getChartData()->getCategories()->clear();

    $workbook = $chart->getChartData()->getChartDataWorkbook();
    $firstCategoryCell = $workbook->getCell(0, 1, 0, "Q1");
    $chart->getChartData()->getCategories()->add($firstCategoryCell);
    $secondCategoryCell = $workbook->getCell(0, 2, 0, "Q2");
    $chart->getChartData()->getCategories()->add($secondCategoryCell);

    $northSeriesCell = $workbook->getCell(0, 0, 1, "North");
    $north = $chart->getChartData()->getSeries()->add($northSeriesCell, $chart->getType());
    $northFirstValueCell = $workbook->getCell(0, 1, 1, 0.25);
    $north->getDataPoints()->addDataPointForBarSeries($northFirstValueCell);
    $northSecondValueCell = $workbook->getCell(0, 2, 1, 0.75);
    $north->getDataPoints()->addDataPointForBarSeries($northSecondValueCell);

    $southSeriesCell = $workbook->getCell(0, 0, 2, "South");
    $south = $chart->getChartData()->getSeries()->add($southSeriesCell, $chart->getType());
    $southFirstValueCell = $workbook->getCell(0, 1, 2, 0.40);
    $south->getDataPoints()->addDataPointForBarSeries($southFirstValueCell);
    $southSecondValueCell = $workbook->getCell(0, 2, 2, 0.60);
    $south->getDataPoints()->addDataPointForBarSeries($southSecondValueCell);

    for ($i = 0; $i < java_values($chart->getChartData()->getSeries()->size()); $i++) {
        $series = $chart->getChartData()->getSeries()->get_Item($i);
        $format = $series->getLabels()->getDefaultDataLabelFormat();
        $format->setShowCategoryName(true);
        $format->setShowSeriesName(true);
        $format->setShowValue(true);
    }

    $north->getLabels()->get_Item(1)->getDataLabelFormat()->setNumberFormatLinkedToSource(false);
    $north->getLabels()->get_Item(1)->getDataLabelFormat()->setNumberFormat("0%");
    $south->getLabels()->get_Item(0)->getTextFrameForOverriding()->setText("Reviewed");

    for ($i = 0; $i < java_values($chart->getChartData()->getSeries()->size()); $i++) {
        $series = $chart->getChartData()->getSeries()->get_Item($i);
        for ($j = 0; $j < java_values($series->getDataPoints()->size()); $j++) {
            $point = $series->getDataPoints()->get_Item($j);
            $label = $point->getLabel();
            if (!java_values($label->isVisible())) {
                continue;
            }

            echo "Value: " . java_values($point->getValue()->getData()) . "; label: " . java_values($label->getActualLabelText()) . PHP_EOL;
        }
    }
} finally {
    $presentation->dispose();
}

数据点中存储的数值仍为 0.75，即使其标签显示为 75% 并附带类别和系列名称。自定义文本会替代生成的标签文本。无论哪种情况，getActualLabelText 都返回最终的标签字符串。请单独检查 isVisible，如上例所示，以在只提取可见标签时使用。

控制轴最大值之外的数据标签

当手动限制坐标轴范围时，某些数据点可能超出其最大值。使用 setShowDataLabelsOverMaximum 来控制是否显示这些数据标签。该设置仅更改标签可见性；不会更改坐标轴范围或底层数据数值。

下面的示例创建一个二维聚簇柱形图，数值为 60 和 120。它对垂直轴调用 setAutomaticMaxValue 并传入 false，随后使用 setMaxValue 将最大值设为 100。第一张幻灯片允许标签超出最大值；复制的幻灯片则禁用此功能。两张幻灯片均保存在 DataLabelsOverMaximum.pptx 中。

使用 setShowValue 启用数值标签。图表级别的设置本身并不会启用数值显示，也不会覆盖单个标签已禁用的数值显示。此示例为整个系列启用数值，并使用 setPosition 将标签放置在每根柱形的外端。

use aspose\slides\Presentation;
use aspose\slides\ChartType;
use aspose\slides\LegendDataLabelPosition;
use aspose\slides\SaveFormat;

$presentation = new Presentation();
try {
    $slide = $presentation->getSlides()->get_Item(0);

    $chart = $slide->getShapes()->addChart(ChartType::ClusteredColumn, 50, 50, 600, 400);
    $chart->setLegend(false);

    $chart->getChartData()->getSeries()->clear();
    $chart->getChartData()->getCategories()->clear();

    $workbook = $chart->getChartData()->getChartDataWorkbook();

    $firstCategory = $workbook->getCell(0, 1, 0, "Within range");
    $secondCategory = $workbook->getCell(0, 2, 0, "Above maximum");

    $chart->getChartData()->getCategories()->add($firstCategory);
    $chart->getChartData()->getCategories()->add($secondCategory);

    $seriesName = $workbook->getCell(0, 0, 1, "Values");
    $series = $chart->getChartData()->getSeries()->add($seriesName, $chart->getType());

    $firstValue = $workbook->getCell(0, 1, 1, 60);
    $secondValue = $workbook->getCell(0, 2, 1, 120);

    $series->getDataPoints()->addDataPointForBarSeries($firstValue);
    $series->getDataPoints()->addDataPointForBarSeries($secondValue);

    $series->getLabels()->getDefaultDataLabelFormat()->setShowValue(true);
    $series->getLabels()->getDefaultDataLabelFormat()->setPosition(LegendDataLabelPosition::OutsideEnd);

    $chart->getAxes()->getVerticalAxis()->setAutomaticMaxValue(false);
    $chart->getAxes()->getVerticalAxis()->setMaxValue(100);
    $chart->setShowDataLabelsOverMaximum(true);

    $secondSlide = $presentation->getSlides()->addClone($slide);
    $secondChart = $secondSlide->getShapes()->get_Item(0);
    $secondChart->setShowDataLabelsOverMaximum(false);

    $presentation->save("DataLabelsOverMaximum.pptx", SaveFormat::Pptx);
} finally {
    $presentation->dispose();
}

以下图片显示了 Microsoft PowerPoint 渲染的保存幻灯片。true 时，标签 120 在上边界可见；false 时，它被隐藏。标签 60 保持可见，坐标轴最大值仍为 100，第二个数据点在两种情况下仍为 120。

setShowDataLabelsOverMaximum(true)	setShowDataLabelsOverMaximum(false)

Chart Type

This example uses a 2D column chart with a value axis. Charts without a value axis, such as pie and doughnut charts, do not have an axis maximum to limit in this way.

设置标签与坐标轴的距离

使用 setLabelOffset 控制分类坐标轴标签与坐标轴之间的距离。该值是标签最大字体大小的百分比。本示例创建一个聚簇柱形图，并将水平坐标轴标签偏移设置为 500。此设置影响分类坐标轴标签，而不是附加到单个数据点的标签。

use aspose\slides\Presentation;
use aspose\slides\ChartType;
use aspose\slides\SaveFormat;

$presentation = new Presentation();
try {
    $slide = $presentation->getSlides()->get_Item(0);

    $chart = $slide->getShapes()->addChart(ChartType::ClusteredColumn, 20, 20, 500, 300);
    $chart->getAxes()->getHorizontalAxis()->setLabelOffset(500);

    $presentation->save("SetCategoryAxisLabelDistance_out.pptx", SaveFormat::Pptx);
} finally {
    $presentation->dispose();
}

调整标签位置

在饼图上，调整数据标签位置以改善间距并为引导线留出空间。

本示例显示第一个数据点的数值，将其标签放在切片外部，并使用 setX 和 setY 调整水平和垂直偏移。这些偏移分别相对于图表宽度和高度。

use aspose\slides\Presentation;
use aspose\slides\ChartType;
use aspose\slides\LegendDataLabelPosition;
use aspose\slides\SaveFormat;

$presentation = new Presentation();
try {
    $slide = $presentation->getSlides()->get_Item(0);
    
    $chart = $slide->getShapes()->addChart(ChartType::Pie, 50, 50, 200, 200);
    $series = $chart->getChartData()->getSeries();

    $label = $series->get_Item(0)->getLabels()->get_Item(0);
    $label->getDataLabelFormat()->setShowValue(true);
    $label->getDataLabelFormat()->setPosition(LegendDataLabelPosition::OutsideEnd);
    $label->setX(0.71);
    $label->setY(0.04);

    $presentation->save("presentation.pptx", SaveFormat::Pptx);
} finally {
    $presentation->dispose();
}

格式化引导线

当饼图标签位于切片外部时，引导线帮助读者将每个数值与对应切片匹配。使用对比色和略微加粗的线条可以让这些连接更易辨认，而透明度和虚线样式则使线条保持视觉上的不突兀。

使用 getLeaderLinesFormat 在系列数据标签集合级别格式化引导线。$series->getLabels()->getLeaderLinesFormat()->getLine() 中的设置作用于整个集合，而不是单个标签。

本示例创建一个默认数据的饼图，显示切片外的数值，并启用 setShowLeaderLines。它使用 setX 和 setY 将两个标签进一步移离切片，偏移以图表宽度和高度的比例表示。无需输入演示文稿。

线条的 getFillFormat 将颜色设为不透明度为 191（满值 255）的纯蓝色，约为 25% 透明度。setWidth 将粗细设为 2 磅，setDashStyle 将线条设为虚线。

use aspose\slides\Presentation;
use aspose\slides\ChartType;
use aspose\slides\LegendDataLabelPosition;
use aspose\slides\FillType;
use aspose\slides\LineDashStyle;
use aspose\slides\SaveFormat;

$presentation = new Presentation();
try {
    $slide = $presentation->getSlides()->get_Item(0);

    $chart = $slide->getShapes()->addChart(ChartType::Pie, 80, 50, 560, 400);
    $chart->setLegend(false);

    $series = $chart->getChartData()->getSeries()->get_Item(0);

    $labelFormat = $series->getLabels()->getDefaultDataLabelFormat();
    $labelFormat->setShowValue(true);
    $labelFormat->setPosition(LegendDataLabelPosition::OutsideEnd);
    $labelFormat->setShowLeaderLines(true);

    // 将两个标签向外移动，使其更远离切片。
    $series->getLabels()->get_Item(0)->setX(0.10);
    $series->getLabels()->get_Item(0)->setY(-0.05);
    $series->getLabels()->get_Item(1)->setX(-0.10);
    $series->getLabels()->get_Item(1)->setY(0.05);

    $line = $series->getLabels()->getLeaderLinesFormat()->getLine();
    $line->getFillFormat()->setFillType(FillType::Solid);
    $lineColor = new Java("java.awt.Color", 30, 90, 160, 191);
    $line->getFillFormat()->getSolidFillColor()->setColor($lineColor);
    $line->setWidth(2);
    $line->setDashStyle(LineDashStyle::Dash);

    $presentation->save("FormattedLeaderLines.pptx", SaveFormat::Pptx);
} finally {
    $presentation->dispose();
}

启用引导线并不保证每个标签都会出现引导线。可见性取决于标签位置和图表的布局行为。在本示例中，两个移位的标签拥有可见的引导线；靠近切片的标签则不需要。

以下图片显示了由 Aspose.Slides 渲染的保存文件 FormattedLeaderLines.pptx：

在柱形图上方添加多行数据标签

本示例创建一个柱形图，在绘图区上方放置两行数据标签。Series A 显示可见的柱形，Series B 和 Series C 提供额外的标签。通过移除填充和轮廓将它们的柱形隐藏。使用 ChartSeriesGroup::setOverlap 方法使三个系列在相同的类别中心对齐。

ChartPlotArea 设置为标签行预留空间。调用 Chart::validateChartLayout 计算默认位置后，使用 DataLabel::setX 和 DataLabel::setY 保持水平对齐并施加垂直偏移，以将标签排列成两行。数字仍然是链接到系列数值的数据标签；只有行标题是独立的文本形状。

use aspose\slides\Presentation;
use aspose\slides\ChartType;
use aspose\slides\FillType;
use aspose\slides\LegendDataLabelPosition;
use aspose\slides\LayoutTargetType;
use aspose\slides\ShapeType;
use aspose\slides\SaveFormat;

$colors = java("java.awt.Color");

$presentation = new Presentation();
try {
    $slide = $presentation->getSlides()->get_Item(0);

    $chart = $slide->getShapes()->addChart(ChartType::ClusteredColumn, 40, 40, 640, 200);
    $chart->setTitle(false);
    $chart->setLegend(false);
    $chart->getTextFormat()->getPortionFormat()->setFontHeight(12);

    $chart->getChartData()->getSeries()->clear();
    $chart->getChartData()->getCategories()->clear();

    $workbook = $chart->getChartData()->getChartDataWorkbook();
    $workbook->clear(0);

    $categories = [ "North", "South", "East", "West" ];
    $seriesNames = [ "Series A", "Series B", "Series C" ];
    $seriesValues = [
        [ 35, 42, 28, 47 ],
        [ 22, 31, 19, 26 ],
        [ 12, 16, 14, 18 ]
    ];
    
    for ($categoryIndex = 0; $categoryIndex < count($categories); $categoryIndex++) {
        $categoryCell = $workbook->getCell(0, $categoryIndex + 1, 0, $categories[$categoryIndex]);
        $chart->getChartData()->getCategories()->add($categoryCell);
    }

    for ($seriesIndex = 0; $seriesIndex < count($seriesNames); $seriesIndex++) {
        $seriesCell = $workbook->getCell(0, 0, $seriesIndex + 1, $seriesNames[$seriesIndex]);
        $series = $chart->getChartData()->getSeries()->add($seriesCell, ChartType::ClusteredColumn);

        for ($categoryIndex = 0; $categoryIndex < count($categories); $categoryIndex++) {
            $valueCell = $workbook->getCell(0, $categoryIndex + 1, $seriesIndex + 1, $seriesValues[$seriesIndex][$categoryIndex]);
            $series->getDataPoints()->addDataPointForBarSeries($valueCell);
        }

        if ($seriesIndex > 0) {
            // 隐藏 B 和 C 的柱形，但保留它们的数据标签。
            $series->getFormat()->getFill()->setFillType(FillType::NoFill);
            $series->getFormat()->getLine()->getFillFormat()->setFillType(FillType::NoFill);
            $labelFormat = $series->getLabels()->getDefaultDataLabelFormat();
            $labelFormat->setShowValue(true);
            $labelFormat->getTextFormat()->getPortionFormat()->setFontHeight(12);
            $labelFill = $labelFormat->getTextFormat()->getPortionFormat()->getFillFormat();
            $labelFill->setFillType(FillType::Solid);
            $labelFill->getSolidFillColor()->setColor($colors->BLACK);
            $labelFormat->setPosition(LegendDataLabelPosition::InsideBase);
        }
    }

    // 将所有三个系列对齐到相同的类别中心。
    $chart->getChartData()->getSeries()->get_Item(0)->getParentSeriesGroup()->setOverlap(100);

    // 在此紧凑示例中使用更少的网格线。
    $chart->getAxes()->getVerticalAxis()->setAutomaticMajorUnit(false);
    $chart->getAxes()->getVerticalAxis()->setMajorUnit(10);

    // 为绘图区上方预留两行数据标签的空间。
    $chart->getPlotArea()->setLayoutTargetType(LayoutTargetType::Inner);
    $chart->getPlotArea()->setX(0.15);
    $chart->getPlotArea()->setY(0.32);
    $chart->getPlotArea()->setWidth(0.80);
    $chart->getPlotArea()->setHeight(0.48);
    $chart->validateChartLayout();

    $chartX = java_values($chart->getX());
    $chartY = java_values($chart->getY());
    $chartHeight = java_values($chart->getHeight());
    for ($seriesIndex = 1; $seriesIndex < count($seriesNames); $seriesIndex++) {
        $series = $chart->getChartData()->getSeries()->get_Item($seriesIndex);
        $rowTop = $seriesIndex == 1 ? 0.15 : 0.03;

        for ($categoryIndex = 0; $categoryIndex < count($categories); $categoryIndex++) {
            $dataLabel = $series->getDataPoints()->get_Item($categoryIndex)->getLabel();
            // 保持默认的水平位置。Y 是相对于
            // 默认标签位置的偏移，以图表高度的比例表示。
            $actualY = java_values($dataLabel->getActualY());
            $dataLabel->setX(0);
            $dataLabel->setY($rowTop - $actualY / $chartHeight);
        }

        // 仅行标题是单独的文本形状。
        $rowHeading = $slide->getShapes()->addAutoShape(ShapeType::Rectangle, $chartX, $chartY + $rowTop * $chartHeight, 85, 18);
        $rowHeading->getFillFormat()->setFillType(FillType::NoFill);
        $rowHeading->getLineFormat()->getFillFormat()->setFillType(FillType::NoFill);
        $rowHeading->addTextFrame($seriesNames[$seriesIndex]);
        $rowHeading->getTextFrame()->getTextFrameFormat()->setMarginTop(0);
        $rowHeading->getTextFrame()->getTextFrameFormat()->setMarginBottom(0);
        $headingFormat = $rowHeading->getTextFrame()->getParagraphs()->get_Item(0)->getPortions()->get_Item(0)->getPortionFormat();
        $headingFormat->setFontHeight(12);
        $headingFormat->getFillFormat()->setFillType(FillType::Solid);
        $headingFormat->getFillFormat()->getSolidFillColor()->setColor($colors->BLACK);
    }

    $presentation->save("multiple-rows-of-labels.pptx", SaveFormat::Pptx);
} finally {
    $presentation->dispose();
}

常见问题

如何防止在密集图表中数据标签重叠？
结合自动标签布局、引导线和减小字体大小；必要时隐藏某些字段（例如类别），或仅为极值或关键点显示标签。

如何仅对零、负数或空值禁用标签？
在启用标签之前过滤数据点，并根据定义的规则关闭对值为 0、负数或缺失的显示。

如何确保导出为 PDF/图像时标签样式一致？
显式设置字体族和大小，并验证渲染环境中已安装该字体，以避免回退。