使用 JavaScript 管理演示文稿中的项目符号和编号列表

概述

Aspose.Slides for Node.js via Java 可让您在 PowerPoint 和 OpenDocument 演示文稿中创建和格式化项目符号列表和编号列表。列表项是段落,其项目符号设置通过段落格式进行控制。

使用 Paragraph 类访问段落级别的列表设置。主要入口是 Paragraph.getParagraphFormat().getBullet(),它返回一个 BulletFormat 对象。通过该对象,您可以设置项目符号类型、符号、图片、颜色、大小、编号样式和起始编号。

本文展示了如何:

  • 创建带自定义符号的项目符号列表
  • 创建图片项目符号
  • 通过设置段落深度创建多级列表
  • 创建编号列表
  • 检查并更改现有演示文稿中的列表格式
  • 在段落文本旁读取实际的列表标记和编号

创建项目符号列表

要创建项目符号列表,向 TextFrame 添加 Paragraph 对象,并将 BulletFormat.setType 设置为 BulletType.Symbol。随后可以设置 BulletFormat.setChar、BulletFormat.getColor 和 BulletFormat.setHeight 来控制项目符号的外观。

下面的 JavaScript 代码演示了如何在幻灯片中创建项目符号列表:

var aspose = aspose || {};
aspose.slides = require("aspose.slides.via.java");
const java = require("java");

function createParagraph(text, bulletColor) {
    const paragraph = new aspose.slides.Paragraph();
    const paragraphFormat = paragraph.getParagraphFormat();
    const bulletFormat = paragraphFormat.getBullet();

    bulletFormat.setType(java.newByte(aspose.slides.BulletType.Symbol));
    bulletFormat.setChar(java.newChar("*"));
    paragraphFormat.setIndent(15);
    bulletFormat.setBulletHardColor(java.newByte(aspose.slides.NullableBool.True));
    bulletFormat.getColor().setColor(bulletColor);
    bulletFormat.setHeight(100);
    paragraph.setText(text);

    return paragraph;
}

const presentation = new aspose.slides.Presentation();
try {
    const slide = presentation.getSlides().get_Item(0);

    const autoShape = slide.getShapes().addAutoShape(aspose.slides.ShapeType.Rectangle, 20, 20, 200, 50);

    const textFrame = autoShape.getTextFrame();
    textFrame.getParagraphs().clear();

    const bulletColor = java.newInstanceSync("java.awt.Color", 205, 92, 92);

    const paragraph1 = createParagraph("The first paragraph", bulletColor);
    textFrame.getParagraphs().add(paragraph1);

    const paragraph2 = createParagraph("The second paragraph", bulletColor);
    textFrame.getParagraphs().add(paragraph2);

    presentation.save("symbol_bullets.pptx", aspose.slides.SaveFormat.Pptx);
} finally {
    presentation.dispose();
}

结果:

符号项目符号

创建编号列表

当项目顺序重要时使用编号列表。将 BulletFormat.setType 设置为 BulletType.Numbered。您还可以使用 BulletFormat.setNumberedBulletStyle 选择编号格式,或在列表应从除 1 之外的值开始时使用 BulletFormat.setNumberedBulletStartWith。

下面的 JavaScript 代码展示了如何在幻灯片中创建编号列表:

var aspose = aspose || {};
aspose.slides = require("aspose.slides.via.java");
const java = require("java");

const presentation = new aspose.slides.Presentation();
try {
    const slide = presentation.getSlides().get_Item(0);

    const autoShape = slide.getShapes().addAutoShape(aspose.slides.ShapeType.Rectangle, 20, 20, 90, 80);

    const textFrame = autoShape.getTextFrame();
    textFrame.getParagraphs().clear();

    const paragraph1 = new aspose.slides.Paragraph();
    paragraph1.getParagraphFormat().getBullet().setType(java.newByte(aspose.slides.BulletType.Numbered));
    paragraph1.setText("Apple");
    textFrame.getParagraphs().add(paragraph1);

    const paragraph2 = new aspose.slides.Paragraph();
    paragraph2.getParagraphFormat().getBullet().setType(java.newByte(aspose.slides.BulletType.Numbered));
    paragraph2.setText("Orange");
    textFrame.getParagraphs().add(paragraph2);

    const paragraph3 = new aspose.slides.Paragraph();
    paragraph3.getParagraphFormat().getBullet().setType(java.newByte(aspose.slides.BulletType.Numbered));
    paragraph3.setText("Banana");
    textFrame.getParagraphs().add(paragraph3);

    presentation.save("numbered_bullets.pptx", aspose.slides.SaveFormat.Pptx);
} finally {
    presentation.dispose();
}

结果:

编号项目符号

创建图片项目符号

Aspose.Slides 允许您用图片替换常规的项目符号符号。图片项目符号最适合使用在小尺寸下仍保持可读性的简洁图像,例如图标或小的透明 PNG 文件。

要创建图片项目符号,使用 Presentation.getImages().addImage 将图片添加到 Presentation,并将返回的 PPImage 对象分配给 BulletFormat.getPicture().setImage。在分配图片之前,将 BulletFormat.setType 设置为 BulletType.Picture。

假设我们有一张 “image.png”:

用于项目符号的图片

下面的 JavaScript 代码展示了如何在幻灯片中创建图片项目符号:

var aspose = aspose || {};
aspose.slides = require("aspose.slides.via.java");
const java = require("java");

function createParagraph(text, image) {
    const paragraph = new aspose.slides.Paragraph();
    const paragraphFormat = paragraph.getParagraphFormat();
    const bulletFormat = paragraphFormat.getBullet();

    bulletFormat.setType(java.newByte(aspose.slides.BulletType.Picture));
    bulletFormat.getPicture().setImage(image);
    paragraphFormat.setIndent(15);
    bulletFormat.setHeight(100);
    paragraph.setText(text);

    return paragraph;
}

const presentation = new aspose.slides.Presentation();
let image = null;
try {
    const slide = presentation.getSlides().get_Item(0);

    const autoShape = slide.getShapes().addAutoShape(aspose.slides.ShapeType.Rectangle, 20, 20, 200, 50);

    const textFrame = autoShape.getTextFrame();
    textFrame.getParagraphs().clear();

    image = aspose.slides.Images.fromFile("image.png");
    const bulletImage = presentation.getImages().addImage(image);

    const paragraph1 = createParagraph("The first paragraph", bulletImage);
    textFrame.getParagraphs().add(paragraph1);

    const paragraph2 = createParagraph("The second paragraph", bulletImage);
    textFrame.getParagraphs().add(paragraph2);

    presentation.save("picture_bullets.pptx", aspose.slides.SaveFormat.Pptx);
} finally {
    if (image !== null) {
        image.dispose();
    }
    presentation.dispose();
}

结果:

图片项目符号

创建多级列表

使用 ParagraphFormat.setDepth 可将列表项放在不同层级。层级 0 为顶层,层级 1 为其下的嵌套,以此类推。

下面的 JavaScript 代码展示了如何创建多级项目符号列表:

var aspose = aspose || {};
aspose.slides = require("aspose.slides.via.java");
const java = require("java");

const presentation = new aspose.slides.Presentation();
try {
    const slide = presentation.getSlides().get_Item(0);

    const autoShape = slide.getShapes().addAutoShape(aspose.slides.ShapeType.Rectangle, 20, 20, 260, 110);

    const textFrame = autoShape.getTextFrame();
    textFrame.getParagraphs().clear();

    const paragraph1 = new aspose.slides.Paragraph();
    paragraph1.getParagraphFormat().setDepth(java.newShort(0));
    paragraph1.setText("My text - Depth 0");
    textFrame.getParagraphs().add(paragraph1);

    const paragraph2 = new aspose.slides.Paragraph();
    paragraph2.getParagraphFormat().setDepth(java.newShort(1));
    paragraph2.setText("My text - Depth 1");
    textFrame.getParagraphs().add(paragraph2);

    const paragraph3 = new aspose.slides.Paragraph();
    paragraph3.getParagraphFormat().setDepth(java.newShort(2));
    paragraph3.setText("My text - Depth 2");
    textFrame.getParagraphs().add(paragraph3);

    const paragraph4 = new aspose.slides.Paragraph();
    paragraph4.getParagraphFormat().setDepth(java.newShort(3));
    paragraph4.setText("My text - Depth 3");
    textFrame.getParagraphs().add(paragraph4);

    presentation.save("multilevel_bullets.pptx", aspose.slides.SaveFormat.Pptx);
} finally {
    presentation.dispose();
}

结果:

多级列表

更改现有列表

要更改现有演示文稿中的列表格式,访问目标段落并更新其 ParagraphFormat.getBullet 设置。创建列表时使用的相同属性也可用于检查或修改从 PPT、PPTX 或 ODP 文件加载的列表。

下面的 JavaScript 代码将文本框中的第一段落更改为使用编号列表样式:

var aspose = aspose || {};
aspose.slides = require("aspose.slides.via.java");
const java = require("java");

const presentation = new aspose.slides.Presentation("input.pptx");
try {
    const slide = presentation.getSlides().get_Item(0);

    const autoShape = slide.getShapes().get_Item(0);

    const paragraph = autoShape.getTextFrame().getParagraphs().get_Item(0);

    const paragraphFormat = paragraph.getParagraphFormat();
    const bulletFormat = paragraphFormat.getBullet();

    bulletFormat.setType(java.newByte(aspose.slides.BulletType.Numbered));
    bulletFormat.setNumberedBulletStyle(java.newByte(aspose.slides.NumberedBulletStyle.BulletRomanUCPeriod));
    bulletFormat.setNumberedBulletStartWith(java.newShort(1));
    paragraphFormat.setMarginLeft(30);
    paragraphFormat.setIndent(-20);

    presentation.save("updated_list.pptx", aspose.slides.SaveFormat.Pptx);
} finally {
    presentation.dispose();
}

读取实际的项目符号值

在提取演示文稿内容时,将列表标记与段落文本一起保留。调用 ParagraphFormat.getEffective 并访问 IParagraphFormatEffectiveData.getBullet 以获取有效的项目符号格式。在读取 getActualBulletValue 之前,先检查其 getType。

对于编号列表,下面这三个值需要区分:

使用每个段落的 getDepth 可保留其嵌套层级。实际标记不编码完整层次结构:嵌套项可能返回 c. 而不是组合标签如 6.c.。

下面的独立示例创建列表、将其保存到演示文稿、重新加载演示文稿并报告每个段落的文本、深度、项目符号类型和实际值。小蓝色图片标记由内联 SVG 创建。

var aspose = aspose || {};
aspose.slides = require("aspose.slides.via.java");
const java = require("java");
const black = java.newInstanceSync("java.awt.Color", 0, 0, 0);

const presentation = new aspose.slides.Presentation();
try {
    presentation.getSlideSize().setSize(720, 440, aspose.slides.SlideSizeScaleType.DoNotScale);
    const slide = presentation.getSlides().get_Item(0);

    const shape = slide.getShapes().addAutoShape(aspose.slides.ShapeType.Rectangle, 30, 20, 660, 400);
    shape.getFillFormat().setFillType(java.newByte(aspose.slides.FillType.NoFill));
    shape.getLineFormat().getFillFormat().setFillType(java.newByte(aspose.slides.FillType.NoFill));

    const textFrame = shape.getTextFrame();
    textFrame.getParagraphs().clear();

    // 创建一个无需外部图像文件的图片标记。
    const svg = new aspose.slides.SvgImage("<svg xmlns='http://www.w3.org/2000/svg' width='16' height='16'><rect width='16' height='16' rx='4' fill='#0078D4'/></svg>");
    const bulletImage = presentation.getImages().addImage(svg);

    function addParagraph(text, depth, type, start, style) {
        const paragraph = new aspose.slides.Paragraph();
        paragraph.setText(text);

        const format = paragraph.getParagraphFormat();
        format.setDepth(java.newShort(depth));
        format.setMarginLeft(30 + depth * 40);
        format.setIndent(-28);
        format.setSpaceAfter(8);
        format.getDefaultPortionFormat().setFontHeight(22);
        format.getDefaultPortionFormat().getFillFormat().setFillType(java.newByte(aspose.slides.FillType.Solid));
        format.getDefaultPortionFormat().getFillFormat().getSolidFillColor().setColor(black);
        format.getBullet().setType(java.newByte(type));
        format.getBullet().setBulletHardColor(java.newByte(aspose.slides.NullableBool.True));
        format.getBullet().getColor().setColor(black);
        if (type === aspose.slides.BulletType.Numbered) {
            format.getBullet().setNumberedBulletStyle(java.newByte(style));
            format.getBullet().setNumberedBulletStartWith(java.newShort(start));
        } else if (type === aspose.slides.BulletType.Symbol) {
            format.getBullet().setChar(java.newChar(0x2022));
        } else if (type === aspose.slides.BulletType.Picture) {
            format.getBullet().getPicture().setImage(bulletImage);
        }

        textFrame.getParagraphs().add(paragraph);
    }

    addParagraph("First item", 0, aspose.slides.BulletType.Numbered, 5, aspose.slides.NumberedBulletStyle.BulletArabicPeriod);
    addParagraph("Second item", 0, aspose.slides.BulletType.Numbered, 5, aspose.slides.NumberedBulletStyle.BulletArabicPeriod);
    addParagraph("Nested item", 1, aspose.slides.BulletType.Numbered, 3, aspose.slides.NumberedBulletStyle.BulletAlphaLCPeriod);
    addParagraph("Next nested item", 1, aspose.slides.BulletType.Numbered, 3, aspose.slides.NumberedBulletStyle.BulletAlphaLCPeriod);
    addParagraph("Deep item", 2, aspose.slides.BulletType.Numbered, 4, aspose.slides.NumberedBulletStyle.BulletRomanLCPeriod);
    addParagraph("Back to top level", 0, aspose.slides.BulletType.Numbered, 5, aspose.slides.NumberedBulletStyle.BulletArabicPeriod);
    addParagraph("Symbol marker", 0, aspose.slides.BulletType.Symbol, 1, aspose.slides.NumberedBulletStyle.BulletArabicPeriod);
    addParagraph("No bullet", 0, aspose.slides.BulletType.None, 1, aspose.slides.NumberedBulletStyle.BulletArabicPeriod);
    addParagraph("Picture marker", 0, aspose.slides.BulletType.Picture, 1, aspose.slides.NumberedBulletStyle.BulletArabicPeriod);
    presentation.save("actual_bullet_values.pptx", aspose.slides.SaveFormat.Pptx);
} finally {
    presentation.dispose();
}

const loadedPresentation = new aspose.slides.Presentation("actual_bullet_values.pptx");
try {
    const loadedShape = loadedPresentation.getSlides().get_Item(0).getShapes().get_Item(0);
    console.log("Text | Depth | Type | Actual value");
    const paragraphs = loadedShape.getTextFrame().getParagraphs();
    for (let i = 0; i < paragraphs.getCount(); i++) {
        const paragraph = paragraphs.get_Item(i);
        const bullet = paragraph.getParagraphFormat().getEffective().getBullet();
        let marker;
        switch (bullet.getType()) {
            case aspose.slides.BulletType.Numbered:
            case aspose.slides.BulletType.Symbol:
                marker = bullet.getActualBulletValue();
                break;
            case aspose.slides.BulletType.None:
                marker = bullet.getActualBulletValue() + " (no bullet)";
                break;
            case aspose.slides.BulletType.Picture:
                marker = bullet.getActualBulletValue() + " (image required)";
                break;
            default:
                marker = "unsupported bullet type";
                break;
        }
        const typeName = Object.keys(aspose.slides.BulletType).find(name => aspose.slides.BulletType[name] === bullet.getType());
        console.log(paragraph.getText() + " | " + paragraph.getParagraphFormat().getDepth() + " | " + typeName + " | " + marker);
    }
} finally {
    loadedPresentation.dispose();
}

下面显示了源列表。

从 5 开始的列表、嵌套的字母和罗马数字项、符号标记、没有项目符号的段落以及蓝色图片标记

报告与 PowerPoint 中显示的标记相匹配:

Text | Depth | Type | Actual value
First item | 0 | Numbered | 5.
Second item | 0 | Numbered | 6.
Nested item | 1 | Numbered | c.
Next nested item | 1 | Numbered | d.
Deep item | 2 | Numbered | iv.
Back to top level | 0 | Numbered | 7.
Symbol marker | 0 | Symbol | •
No bullet | 0 | None | null (no bullet)
Picture marker | 0 | Picture | null (image required)

对于 BulletType.None and BulletType.Picture,getActualBulletValue 返回 null,而不是空字符串。请分别处理这些类型:前者没有标记,后者需要单独提取项目符号图片。仅通过提取文本标记无法再现图片项目符号。

常见问题解答

项目符号列表和编号列表可以导出为 PDF 或图片吗?

可以。Aspose.Slides 在目标格式支持相应的文本布局和项目符号功能时,会保留列表格式。

我可以编辑现有演示文稿中的列表吗?

可以。加载演示文稿,访问目标段落,检查或更新其 ParagraphFormat.getBullet 设置,然后保存演示文稿。

列表可以包含非拉丁文字吗?

可以。列表项文本可以包含 Unicode 字符,您可以在多语言演示文稿中创建列表。请确保演示文稿使用的字体支持所需字符。