我是.NET开发人员,因此代码在C#中.但是你应该能够轻松翻译以下内容.

iText是一个PDF优先的库,[X] HTML解析非常复杂,因此在这方面并不完整.每当解析[X] HTML并且事情不按预期的方式进行特定标记时,您应遵循的基本步骤是：

>验证XML Worker支持标记：Tags class.

>如果支持标记(在本例中为true),请查看默认实现.这里由the HorizontalRule class处理.但是,我们看到不支持您的用例,所以一种方法是使用该代码作为蓝图. (如下所示)您还可以继承特定的标记类并覆盖End()方法as done here.无论哪种方式,您所做的只是实现自定义标记处理器.

>如果不支持该标记,则需要通过继承AbstractTagProcessor来滚动自己的自定义标记处理器.

无论如何,这是一个让你入门的简单例子.首先,自定义标签处理器：

public class CustomHorizontalRule : AbstractTagProcessor

{

public override IList Start(IWorkerContext ctx, Tag tag)

{

IList result;

LineSeparator lineSeparator;

var cssUtil = CssUtils.GetInstance();

try

{

IList list = new List();

HtmlPipelineContext htmlPipelineContext = this.GetHtmlPipelineContext(ctx);

Paragraph paragraph = new Paragraph();

IDictionary css = tag.CSS;

float baseValue = 12f;

if (css.ContainsKey("font-size"))

{

baseValue = cssUtil.ParsePxInCmMmPcToPt(css["font-size"]);

}

string text;

css.TryGetValue("margin-top", out text);

if (text == null) text = "0.5em";

string text2;

css.TryGetValue("margin-bottom", out text2);

if (text2 == null) text2 = "0.5em";

string border;

css.TryGetValue(CSS.Property.BORDER_BOTTOM_STYLE, out border);

lineSeparator = border != null && border == "dotted"

? new DottedLineSeparator()

: new LineSeparator();

var element = (LineSeparator)this.GetCssAppliers().Apply(

lineSeparator, tag, htmlPipelineContext

);

string color;

css.TryGetValue(CSS.Property.BORDER_BOTTOM_COLOR, out color);

if (color != null)

{

// WebColors deprecated, but docs don't state replacement

element.LineColor = WebColors.GetRGBColor(color);

}

paragraph.SpacingBefore += cssUtil.ParseValueToPt(text, baseValue);

paragraph.SpacingAfter += cssUtil.ParseValueToPt(text2, baseValue);

paragraph.Leading = 0f;

paragraph.Add(element);

list.Add(paragraph);

result = list;

}

catch (NoCustomContextException cause)

{

throw new RuntimeWorkerException(

LocaleMessages.GetInstance().GetMessage("customcontext.404"),

cause

);

}

return result;

}

}

大多数代码直接取自现有的源代码,但CSS.Property.BORDER_BOTTOM_STYLE和CSS.Property.BORDER_BOTTOM_COLOR的检查除外,如果它们在< hr>中内联,则设置边框样式和颜色.样式属性.

然后将上面的自定义标记处理器添加到XML Worker TagProcessorFactory：

using (var stream = new FileStream(OUTPUT_FILE, FileMode.Create))

{

using (var document = new Document())

{

var writer = PdfWriter.GetInstance(document, stream);

document.Open();

var tagProcessorFactory = Tags.GetHtmlTagProcessorFactory();

// custom tag processor above

tagProcessorFactory.AddProcessor(

new CustomHorizontalRule(),

new string[] { HTML.Tag.HR }

);

var htmlPipelineContext = new HtmlPipelineContext(null);

htmlPipelineContext.SetTagFactory(tagProcessorFactory);

var pdfWriterPipeline = new PdfWriterPipeline(document, writer);

var htmlPipeline = new HtmlPipeline(htmlPipelineContext, pdfWriterPipeline);

var cssResolver = XMLWorkerHelper.GetInstance().GetDefaultCssResolver(true);

var cssResolverPipeline = new CssResolverPipeline(

cssResolver, htmlPipeline

);

var worker = new XMLWorker(cssResolverPipeline, true);

var parser = new XMLParser(worker);

var xHtml = "

---

";

using (var stringReader = new StringReader(xHtml))

{

parser.Parse(stringReader);

}

}

}

有一点需要注意的是,即使我们使用的是速记边框内联样式,iText的CSS解析器似乎也会在内部设置所有样式.即,您可以使用四种速记样式中的任何一种来检查 – 我恰好使用了CSS.Property.BORDER_BOTTOM_STYLE和CSS.Property.BORDER_BOTTOM_COLOR.

结果PDF：