springboot+vue项目使用Itext实现html转pdf功能

Spring Boot + Vue项目中，使用iText库实现HTML转PDF的功能通常需要以下几个步骤：

1. 添加依赖：首先在Spring Boot项目的pom.xml中添加iText和相关的HTML处理库如HtmlWorker（用于解析HTML）：

<dependency>
    <groupId>com.itextpdf</groupId>
    <artifactId>itextpdf</artifactId>
    <version>5.5.13</version>
</dependency>
<dependency>
    <groupId>net.sf.xhtmlrenderer</groupId>
    <artifactId>xhtmlrenderer-flying-saucer-pdf</artifactId>
    <version>9.0.14</version>
</dependency>

2. 创建服务类：创建一个Java服务类，例如`PdfGeneratorService`，利用iText的HtmlWorker将HTML内容转换为BufferedOutputStream，然后保存为PDF文件：

import com.itextpdf.text.Document;
import com.itextpdf.text.Paragraph;
import com.itextpdf.text.pdf.PdfWriter;
import net.sourceforge.htmlcleaner.TagNode;
import org.apache.commons.io.IOUtils;

public class PdfGeneratorService {
    public byte[] generatePdfFromHtml(String htmlContent) throws Exception {
        Document document = new Document();
        try (OutputStream out = new ByteArrayOutputStream()) {
            PdfWriter.getInstance(document, out);
            document.open();

            // 使用HTMLCleaner清理HTML并转换为TagNode列表
            Cleaner cleaner = new Cleaner();
            List<TagNode> tagNodes = cleaner.clean(htmlContent);

            for (TagNode node : tagNodes) {
                if (node instanceof Paragraph) {
                    document.add((Paragraph) node);
                } else {
                    throw new IllegalArgumentException("Unsupported HTML element found");
                }
            }

            document.close();
            return out.toByteArray();
        }
    }
}

3. 在Vue组件中调用服务：在Vue前端，通过axios或其他HTTP客户端向Spring Boot后端发送POST请求，传入HTML内容，接收返回的PDF数据：

methods: {
    convertToPdf() {
        axios.post('/api/generate-pdf', { htmlContent: this.htmlData })
            .then(response => {
                // 处理PDF数据
                let pdfBlob = new Blob([response.data], { type: 'application/pdf' });
                let linkElement = document.createElement('a');
                linkElement.href = window.URL.createObjectURL(pdfBlob);
                linkElement.download = 'output.pdf';
                linkElement.click();
            })
            .catch(error => console.error(error));
    }
}